Best-track Dataset Research Articles

Vertical structures of typhoon cloud microphysical and radiative features associated with the precipitation type over the western North Pacific

Intensity of different precipitation types (convective, stratiform and shallow) and associated cloud vertical microphysical and radiative heating features are analyzed considering typhoon development, maturity, and decaying stages over the western North Pacific using the CloudSat Tropical Cyclone and China Meteorological Administration tropical cyclone best-track datasets from 2 June 2006 to 31 December 2015. At all three stages, the convective precipitation intensity, approximately twice that of stratiform precipitation, is the highest and peaks at development stage. The strongest stratiform precipitation occurs at typhoon maturity stage. Shallow precipitation is the weakest throughout the typhoon lifespan. Although the cloud microphysical parameters (radar reflectivity, cloud ice particle number concentration and effective radius) of both convective and stratiform precipitation tend to increase with precipitation intensity, convective precipitation contains more ice water of larger sizes in upper layers than stratiform precipitation. Unlike convective and stratiform precipitation, dominated by cold clouds, shallow precipitation is dominated by warm clouds with weak vertical contrast in the radiative distribution but strong radiation nearby 5 km. Our results show that cloud ice particle number concentration is important not only in precipitation intensity enhancement but also in determining the shortwave radiative heating center vertical location. More and larger ice particles in convective precipitation profiles result in stronger or comparable shortwave radiative heating than those in stratiform precipitation profiles, while the longwave radiative cooling rates in convective and stratiform precipitation profiles exhibit very similar features, likely attributable to similar infrared radiation levels due to comparable temperatures in these profiles.

A study on radial characteristics of North Indian Ocean tropical cyclones and associated energy indices through numerical modeling

The structural characteristics of North Indian Ocean (NIO) Tropical Cyclones (TCs) are emphasized in this study by adopting Weather Research and Forecasting (WRF) numerical modeling framework. TCs that occurred during 2001–2020, were simulated using WRF model in the CTRL, and scatterometer wind vortices from four satellites were considered for assimilation purpose in the WRFDA experiment. Considering the results from both types of simulations, best-track data sets, and ERA5 global analyses, several aspects including radial parameters, the thermodynamic and dynamic properties, horizontal structure, etc., were analyzed besides developing some robust empirical relationships. In the process, model performance was evaluated too. The study emphasized on sub-basin, sectorial, intensity-based, range-based, and frequency-based analysis for the radial parameters. Also, yearly, and seasonal variations were considered, inter-comparisons were carried out, the inter-relationships with numerous environmental and storm-related characteristics have been explored. The study provides valuable insights into the TC radial characteristics over NIO, and associated thermodynamic and dynamic behavior. It upholds that the relatively greater intensity TCs occurring during October–November months are mostly observed to have genesis over the East Arabian Sea (EAS), Middle Bay of Bengal (MBOB), and North Bay of Bengal (NBOB) sectors. The EAS region exhibits higher values for the energy indices and maximum sustained wind (MSW), compared to the Western Arabian Sea (WAS), while the maximum convective potential values show an opposite trend. The assimilation of scatterometer wind data has a limited impact on model results, although it is more effective over the Arabian Sea (AS) than the Bay of Bengal (BOB). WRFDA could provide a relatively better estimate for most of the TC radial features over both AS and BOB. The extensive analysis of TC radial features facilitated developing several empirical relationships involving radial characteristics, MSW and minimum central pressure, which are valid for NIO region.

Tropical cyclone activities in the Western North Pacific in 2022

Based on the best-track dataset from the Shanghai Typhoon Institute/China Meteorological Administration, the paper provides a comprehensive summary and analysis of tropical cyclone (TC) activities in the Western North Pacific (WNP) and the South China Sea (SCS) for 2022. Using the historical climatology from 1951 to 2020, the anomalous conditions during 2022 in TC frequency, origin locations, tracks, intensity, and duration for the entire ocean basin as well as landfall events in China are examined. Results show that the overall TC frequency is slightly lower than normal, but the multiple TC events have a very high frequency of occurrence. Origin locations of TCs, which mark the starting points of their paths, show a large westward and northward deviation from climatology. Around 40% of the named TCs exhibit a shift in their direction of movement from westerly to easterly. Additionally, comparisons of the means, medians, upper and lower quartiles all indicate that the intensity of TCs in 2022 is generally lower than the climatology, with the duration of TCs at tropical storm intensity or above being shorter than usual. A notable observation is the fewer incidence of TC landfalls in China, but with a geographical concentration in Guangdong Province. These anomalous annual TC activities are influenced by related atmospheric and oceanic environmental conditions modulated by multi-scale climate variability. The findings provide useful information for enhancing disaster mitigation strategies in the Asia-Pacific region.

Comprehensive Investigation on Spatiotemporal Variations of Tropical Cyclone Activities in the Western North Pacific, 1950–2019

Tropical Cyclones (TCs) are the most severe natural disasters in the Western North Pacific Ocean (WNP). While previous studies reported evident changes over certain regions or seasons between typical periods, there is a lack of a complete picture of the long-term variations in TC activities in the WNP. This study carried out a comprehensive investigation on the spatiotemporal variations in TC genesis locations and transit pathways in the WNP, based on the TC best-track datasets from the China Meteorological Administration Shanghai Typhoon Institute. The results showed that the TC genesis and occurrence frequencies showed drastic decreases and westward shifts in the WNP from 1950 to 2019. The greatest decrease in TC genesis occurred for Tropical Depressions (TDs: 10.8−17.1 m/s) and Typhoons (TYs: > 32.7 m/s). The number of Tropical Storms (TSs: 17.2−32.6 m/s) and the mean intensity (2 min maximum sustained wind speed) of TCs overall showed no evident change. The decadal average of TC genesis frequency increased by 63% in the near-coast seas (WNPO), but decreased by 46% near the central Pacific Ocean (WNCP), demonstrating a westward shift for TC genesis locations. The TC genesis and occurrence frequencies also showed significant declines in the southern Philippine Sea (SPS) and South China Sea (SCS), while they showed a lower reduction in the Eastern East China Sea (EECS), the northern ocean edge of TC genesis areas, resulting in an increase in the average latitude of TC genesis locations, a spurious northward shift. The La Niña and El Niño years showed contrasting effects on TC genesis frequency and landfall ratios. There were greater instances of TC genesis and greater landfall ratios during the La Niña mature phase, while there were fewer TC formations and lower landfall ratios during the short duration (SD) El Niño developing phase. The TC genesis locations showed a distinct northwestward shift during La Niña years compared to those during El Niño years.

Spatial patterns of typhoon rainfall and associated flood characteristics over a mountainous watershed of a tropical island

The spatial distribution of rainfall in a watershed has an important impact on flood warning and forecasting. In this study, we used the K-means++ clustering method to classify the spatial characteristics of typhoon rainfall events in the Songtao reservoir watershed in the central region of Hainan Island, based on 63 typhoon rainfall event data from 1990 to 2020. Then, the relationship between the synoptic fields, spatial patterns of rainfall, and flood characteristics was explained based on tropical cyclone best-track datasets, atmospheric reanalysis data, and inflow flood series. The results showed that there are three types of cumulative rainfall patterns in the Songtao Reservoir watershed. The heavy rainfall region of pattern 1 is concentrated east of the watershed, whereas the heavy rainfall regions of pattern 2 are mainly concentrated southwest and east of the watersheds of many mountains. The heavy rainfall region of pattern 3, with a southwest-northeast orientation, is located on the west side of the watershed. The spatial coefficient of variation and index of rainfall location clearly distinguished among these three patterns. The composite analysis of typhoon tracks, wind fields, and moisture flux fields can be used to interpret the formation mechanism of these spatial patterns of rainfall events in the watershed. The spatial patterns of cumulative rainfall for each type were dominated by one or two types of hourly spatial rainfall patterns. Flood events resulting from cumulative rainfall patterns 1 and 2 have similar flood behavior metrics. Large floods in the watershed show an obvious seasonal variation, and the corresponding rainfall events mostly show the spatial characteristics of the cumulative rainfall pattern 3. These results can enhance the understanding of the linkage between typhoons, mountainous watershed rainfall, and flooding processes.

Enhanced understanding of changes in tropical cyclones’ landfall frequency over mainland China

The climatological characteristics and interannual variations of tropical cyclones (TCs) making landfall in mainland China during the peak TC seasons (July–October) from 1980 to 2020 are examined using the China Meteorological Administration (CMA) best-track dataset. There were 270 TCs landfalling in mainland China during the study period, with 226 TCs landfalling in South China (SC) and 44 TCs landfalling in East China (EC). During 1980–2020, the number of TCs affecting mainland China gradually decreased, although the trend is not significant. The number of TCs impacting SC is experiencing a significant decrease, while the number of TC affecting EC is stable. Based on the change-point analysis, the TC landfall frequency in mainland China and SC incurred significant decreases in 1995/1996 and 1996/1997, respectively. The significant reduction in the number of landfalling TCs over SC and the insignificant reduction in the TC landfall frequency over mainland China are mainly due to the great reduction in the TC formation frequency over the western North Pacific (WNP). Meanwhile, the yearly mean of TCs’ landfalling latitudes is moving northward slightly, possibly linked to the slight poleward shift of their genesis locations. A large area of negative anomalies in the lower-tropospheric absolute vorticity and positive variations in the vertical wind shear (VWS) over the tropical WNP are possibly responsible for the reduction in TC genesis over the WNP. Moreover, the apparent opposite anomalies of the two variables over the region north of 20°N and south of 20°N might contribute to the slight poleward shift of genesis locations of landfalling TCs during the 41 years. The variations in the large-scale steering flow are favorable for more TCs moving northwestward and making landfall in EC than before. Meanwhile, the decrease in TC landfall frequency over mainland China is found to be significantly correlated to the pronounced warming over the tropical Indian Ocean.

A Survey of Statistical Relationships between Tropical Cyclone Genesis and Convectively Coupled Equatorial Rossby Waves

Convectively coupled equatorial Rossby waves (ERW) modulate tropical cyclone activities over tropical oceans. This study presents a survey of the statistical relationship between intraseasonal ERWs and tropical cyclone genesis (TCG) over major global TC basins using four-decade-long outgoing longwave radiation (OLR) and TC best-track datasets. Intraseasonal ERWs are identified from the OLR anomalies using an empirical orthogonal function (EOF) analysis method without imposing equatorial symmetry. We find that westward-propagating ERWs are most significant in four tropical ocean basins over the summer hemisphere and that ERWs exhibit similar northeast-southwest (southeast-northwest) tilted phase lines in the northern (southern) hemisphere, with an appreciable poleward advance of wave energy in most TC basins. The EOF-based ERW indices quantitatively show that ERWs significantly modulate TC genesis. The convectively active (suppressed) phases of ERWs coincide with increased (reduced) TCG occurrences. The TCG modulation by ERWs achieves the maximum where the ERWs propagate through the climatological TCG hotspots. As a result, the total number of TCG occurrences in the TC basins varies significantly according to the ERW phase. The ERW-TCG relationship is significant over the northwestern Pacific Ocean, northeastern Pacific Ocean, and the northern Indian Ocean during the northern summer seasons. In the southern summer season, the ERW-TCG relationship is significant over the southern Indian Ocean, Indonesian-Australia basin, and the southwestern Pacific Ocean. However, ERW activities are weak in the main TC development region of the Atlantic Ocean; and the impact on Atlantic TCG appears to be insignificant.

A statistical–parametric model of tropical cyclones for hazard assessment

Abstract. We present the formulation of an open-source, statistical–parametric model of tropical cyclones (TCs) for use in hazard and risk assessment applications. The model derives statistical relations for TC behaviour (genesis rate and location, intensity, speed and direction of translation) from best-track datasets, then uses these relations to create a synthetic catalogue based on stochastic sampling, representing many thousands of years of activity. A parametric wind field, based on radial profiles and boundary layer models, is applied to each event in the catalogue that is then used to fit extreme-value distributions for evaluation of return period wind speeds. We demonstrate the capability of the model to replicate observed behaviour of TCs, including coastal landfall rates which are of significant importance for risk assessments.

Atmospheric moisture shapes increasing tropical cyclone precipitation in southern China over the past four decades

Although slower translation speed can induce a larger amount of local rainfall for an individual tropical cyclone (TC), whether change in total TC precipitation (TCP) affecting China is related to TC translation speed in the satellite era remains unclear. Based on multiple TC best-track datasets and a reanalysis dataset, we find a significant increasing trend in total TCP over two regions of southern China during 1980–2018. This upward trend can be attributed to the enhancing atmospheric water vapor content and moisture transport over southern China, however, TC intensity, frequency, and translation speed have no contributions. Given the potential linkage between the increasing atmospheric water vapor content over southern China and the western Pacific warming under global warming, our results suggest a likely role of anthropogenic global warming in the increasing TCP over southern China during the past 4 decades.

Evaluation of Simulation Capability for Multiple Tropical Cyclone Events in the Western North Pacific of the UH_HCM Model

The intraseasonal variability of multiple tropical cyclone (MTC) events in the western North Pacific (WNP) during 1979–2015 is analyzed using the best-track dataset archived at the Joint Typhoon Warning Center. MTC events are divided into three phases according to the time intervals of the tropical cyclone (TC) genesis, that is, active, normal, and inactive phases. Composite analysis results indicate that MTC events tend to occur in the active phase when the monsoon trough is stronger and located farther north than at other times. Initialized by the data from a 10-year stable running result, a 12-year control experiment is carried out using the hybrid atmosphere–ocean coupled model developed at the University of Hawaii (UH_HCM model) to evaluate its simulation capability. Compared with the climate observations, the model shows good skill in simulating the large-scale environmental conditions in the WNP, especially the subtropical high and the monsoon trough. In addition, the model can well simulate the climate characteristics of TCs in the WNP, as well as the differences in each MTC phase. However, the simulated frequency of TCs is less and their locations are more northeast, compared with the observations. The vorticity and moisture in the model appear to be the two main factors affecting MTC activity based on analyses of the genesis potential index.

A beta-advection typhoon track model and its application for typhoon hazard assessment

Typhoon track model plays an important role in typhoon wind hazard estimation. In this article, a beta-advection model is developed to simulate the typhoon track over the western North Pacific (WNP). The typhoon motion is driven by two effects, the steering flow and beta drift. The steering flow is modeled as the linear combination of the 850 ​hPa height large scale flow and 250 ​hPa height large scale flow. The spatially varying weights are estimated from the 20th Century Reanalysis dataset for each 5 ​° ​× ​5 ​° square in WNP. The large scale flows at both heights are simulated as multivariate random process based on the fact that the energy spectrum of the geostrophic turbulence follows a “-3” power law. As another driving force of typhoon motion, the beta drift is calculated by solving the non-divergent barotropical vorticity equation. The adequacy of the present model is validated by the comparison between the typhoon translation velocity inferred from the best-track dataset and that simulated by the model. Finally, integrated with an intensity model, the beta-advection model is used to analyze the statistics of typhoon key parameters and typhoon wind hazard along the southeast coast of mainland China.

Western North Pacific tropical cyclone track forecasts by a machine learning model

An ensemble machine learning model for tropical cyclone (TC) track forecasts over the Western North Pacific was developed and evaluated in this study. First, we investigated predictors including TC climatology and persistence factors which were extracted from TC best-track dataset and storm’s surrounding atmospheric conditions which were extracted from ERA-Interim reanalysis. Then, we built a Gradient Boosting Decision Tree (GBDT) nonlinear model for TC track forecasts, in which 30-year data was used. Finally, using tenfold cross-validation method, the GBDT model was compared with a frequently used technique: climatology and persistence (CLIPER) model. The experimental results show that the GBDT model performs well in three forecast times (24 h, 48 h, and 72 h) with relatively small forecast error of 138, 264, and 363.5 km, respectively. The model obtains excellent TC moving direction aspects. However, the model is still insufficient to produce aspects of storm acceleration and deceleration, with mean moving velocity sensitivities all less than 60%. Nevertheless, the model obtains much more robust and accurate TC tracks relative to CLIPER model, where the forecast skills are 17.5%, 26.3%, and 32.1% at three forecast times, respectively. The presented study demonstrates that the GBDT model could provide reliable evidence and guidance for operational TC track forecasts.

Establishment of an Objective Standard for the Definition of Binary Tropical Cyclones in the Western North Pacific

To develop an objective standard for defining binary tropical cyclones (BTCs) in the western North Pacific (WNP), two best-track datasets, from the China Meteorological Administration and the Joint Typhoon Warning Center, were adopted for statistical analyses on two important characteristics of BTCs—two TCs approaching each other, and counterclockwise spinning. Based on the high consistency between the two datasets, we established an objective standard, which includes a main standard for defining BTCs and a secondary standard for identifying typical/atypical BTCs. The main standard includes two requirements: two coexisting TCs are a pair of BTCs if (i) the separation distance is ⩽ 1800 km, and (ii) this separation maintains for at least 12 h. Meanwhile, the secondary standard defines a typical BTC as one for which there is at least one observation when the two TCs approach each other and spin counterclockwise simultaneously. Under the standard, the ratio of typical BTCs increases as the BTC duration increases or the minimum distance between the two TCs decreases. Then, using the JTWC dataset, it was found that there are 505 pairs of BTCs during the period 1951–2014, including 328 typical BTCs and 177 atypical BTCs, accounting for 65.0% and 35.0% of the total, respectively. In addition, a study of two extreme phenomena—the maximum approaching speed and the maximum counterclockwise angular velocity in typical BTCs—shows that the configuration of the circulation conditions and the distribution of the BTCs favor the formation of these extreme phenomena.

Analysis of Extreme Wind Speed Estimates in the Northern South China Sea

AbstractAn increasing number of coastal and offshore structures have been built for coastal protection and marine development in recent years, and these marine structures need to be reasonably designed on the basis of wind speed. In this paper, extreme wind speed estimates are studied in detail by using the best-track datasets of northwestern Pacific Ocean tropical cyclones and ERA5 wind field data. The extreme wind speed fits by five distributions are compared using a blended sample of the wind fields from the ERA5 dataset and parametric wind data. The blend of wind fields improved the data accuracy and extreme value estimation reliability. In addition, the effects of the distribution model, data, threshold, and parameter estimation methods on the calculated results are discussed. The results show that the data had the greatest influences on probability prediction, followed by the distribution model and the parameter estimation method, with the threshold presenting the least influence. In this study, the reliability of the estimates was improved and the uncertainty of the results was analyzed, and the findings provide a wind speed design reference for the northern South China Sea.

Changes in Tropical-Cyclone Translation Speed over the Western North Pacific

The trend of tropical-cyclone (TC) translation speed is a hot topic recently. Changes in TC translation speed during 1949–2017 over the western North Pacific are analyzed using two best-track datasets here. The TC translation speed decreased during 1949–2017, but there was no significant trend after 1981. The TC translation speed also changes with latitude and intensity. In the tropical ocean, TC translation speed decreased by 5.9% during 69-year recording period. North of 23.5° N, the changes in translation speed is highly consistent with the latitude of TC occurrence. The translation speed of tropical depressions showed no significant trend during the period 1949–2017, but the translation speed of typhoons decreased over the 69-year recording period. The period 1949–1981 contributed most of the slowdown trend. There also was an increase in the frequency of typhoons with translation speed slower than 6 m/s. The decrease of translation speed of typhoons before 1981 was likely caused by the weakening of the summertime tropical circulation.

Impact of Anthropogenic Climate Change on United States Major Hurricane Landfall Frequency

Although anthropogenic climate change has contributed to warmer ocean temperatures that are seemingly more favorable for Atlantic hurricane development, no major hurricanes made landfall in the United States between 2006 and 2016. The U.S., therefore, experienced a major hurricane landfall drought during those years. Using the high-resolution Geophysical Fluid Dynamics Laboratory 25 km grid High-Resolution Forecast-Oriented Low Ocean Resolution (HiFLOR) global climate model, the present study shows that increases in anthropogenic forcing, due to increases in greenhouse gasses, are associated with fewer long-duration major hurricane landfall droughts in the U.S., which implies an increase in major hurricane landfall frequency. We create six different fixed-distance ‘buffers’ that artificially circle the United States coastline in 100 km radial increments and can compensate for the bias in hurricane landfall calculations with six-hourly datasets. Major hurricane landfall frequencies are computed by applying the buffer zones to the six-hourly observed and simulated storm track datasets, which are then compared with the observed recorded major hurricane frequencies. We found that the major hurricane landfall frequencies generated with the 200 km buffer using the six-hourly observed best-track dataset are most correlated with the observed recorded major hurricane landfall frequencies. Using HiFLOR with an implemented buffer system, we found less frequent projections of long-duration major hurricane landfall drought events in controlled scenarios with greater anthropogenic global warming, which is independent on the radius of the coastal buffer. These results indicate an increase in U.S. major hurricane landfall frequencies with an increase in anthropogenic warming, which could pose a substantial threat to coastal communities in the U.S.

Detecting Intensity Evolution of the Western North Pacific Super Typhoons in 2016 Using the Deviation Angle Variance Technique with FY Data

This paper analyzes the complete lifecycle of super typhoons in 2016 in the western North Pacific (WNP) using the deviation angle variance technique (DAV-T). Based on the infrared images from Fengyun (FY) satellites, the DAV-T enables quantification of the axisymmetry of tropical cyclones (TCs) by using the DAV values; and thus, it helps improve the capability of TC intensity estimation. Case analyses of Super Typhoons Lionrock and Meranti were performed to explore the distribution characteristics of the DAV values at the various stages of TC evolution. The results show that the minimum DAV values (i.e., map minimum values: MMVs) gradually decreased and their locations constantly approached the circulation center with enhancement of the TC organization; however, when a ring or disk structure was formed around a TC, significant changes in MMV locations were no longer observed. Nonetheless, when large-scale non-closed deep convective cloud clusters appeared at the early stage or the dissipation stage of the typhoon, the axisymmetry of the TC was poor and the MMV locations tended to lie in the most convective region rather than in the TC circulation center. Overall, the MMVs and their locations, respectively, exhibited a strong correlation with the TC intensity and circulation center, and the correlation increased as the TCs became stronger. Combined with the China Meteorological Administration BestTrack dataset (CMA-BestTrack), statistical analysis of all research samples reveals that the correlation coefficient between the MMVs and maximum surface wind speeds (Vmax) was–0.80; the root mean square error (RMSE) of relative distance between the MMV locations and TC centers was 140.3 km; and especially, when the samples below the tropical depression (TD) intensity were removed, the RMSE of the relative distance decreased dramatically to 95.0 km. The value and location of the MMVs could be used as important indicators for estimating TC intensity and center.

An Objective Tropical Cyclone Intensity Estimation Model Based on Digital IR Satellite Images

ABSTRACT An objective tropical cyclone (TC) intensity estimation model is proposed based on the statistical relationship between TC intensity and its inner-core convection, plus the persistence of TC intensity. In the model, the inner-core convection is described by several parameters retrieved from digital infrared (IR) satellite images, including the number of convective cores (Num), their distance to the TC center, and their blackbody temperature (TBB), among others. The persistence of TC intensity is embodied by the TC intensity six hours previous (V6h). The model was set up by the stepwise regression technique using a five-year dataset (2006-2010) and was tested using an independent dataset covering 2011-2012, with V6h from the best-track dataset. Selected factors of the model included V6h, Num, Lat (TC center latitude), Lon (TC center longitude), DISmin (minimum distance between convective cores and TC center), and TBBdif (difference between the maximum and minimum TBB value of convective cores). Results showed that, for independent samples during 2011-2012, the MAE (mean absolute error) and RMSE (root-mean-square error) of Vmax estimation were 1.8 m s− 1 and 2.4 m s− 1, respectively. In order to make the model totally independent from the best-track dataset, the model estimation from six hours previous was used as the V6h for a second independent test covering 2011-2012. The results showed that the model had an MAE and RMSE of 5.4 m s− 1 and 7.3 m s− 1, respectively. Large errors were found for strong TCs (Severe Typhoon or Super Typhoon). The error statistics of the proposed model are comparable to published statistics on the widely used Dvorak technique or its objective versions, implying its potential to be used as an alternative tool for TC intensity estimation in either real-time operation or post-season best-track analyses.

Application of Dvorak Technique During the Weakening Stage of Tropical Cyclones

ABSTRACT The Dvorak technique has been widely used by operational warning centres around the world as a major analysis tool to determine the intensity of a tropical cyclone (TC). However, there exist noticeable differences in the application of the technique among different warning centres. In particular, the weakening rules in the technique that governs the determination of TC intensity during the TC weakening stage constitute one such difference and are the subject of review in this paper. Three options to modify the weakening rules are introduced and evaluated based on verification against the best-track datasets from various centres.

Association of the Poleward Shift of East Asian Subtropical Upper-Level Jet with Frequent Tropical Cyclone Activities over the Western North Pacific in Summer

The NCEP–NCAR reanalysis dataset and the tropical cyclone (TC) best-track dataset from the Regional Specialized Meteorological Center (RSMC) Tokyo Typhoon Center were employed in the present study to investigate the possible linkage of the meridional displacement of the East Asian subtropical upper-level jet (EASJ) with the TC activity over the western North Pacific (WNP). Results indicate that summertime frequent TC activities would create the poleward shift of the EASJ through a stimulated Pacific–Japan (PJ) teleconnection pattern as well as the changed large-scale meridional temperature gradient. On the contrary, in the inactive TC years, the EASJ is often located more southward than normal with an enhanced intensity. Therefore, TC activities over the WNP are closely related to the location and intensity of the EASJ in summer at the interannual time scale.