Tropical Storm Calvin Eyes Hawaii; Typhoon Talim Impacting Southern China & Vietnam
Just days ago, Hurricane Calvin reached major hurricane status, peaking as a category 3 with sustained winds of 125 miles per hour [1, 2]. Located in the vast expanse of the Pacific Ocean, the storm looked in its early stages to be a “fish storm,” not directly impacting any land areas. However, Calvin, now a tropical storm, is expected to come very close to the Big Island of Hawaii. See the latest forecast from KinetiCast™ below:
Projected wind swath of Tropical Storm Calvin, generated by KinetiCast™ models using forecast data from the National Hurricane Center (NHC). The filled in circles represent the past/forecast path of the cyclone color-coded by intensity.
Fortunately, the latest official forecast from the U.S. National Hurricane Center calls for Calvin to be a minimal tropical storm on its approach to the Big Island [1]. This forecast suggests there is the potential for showery rains, localized flooding, and wind gusts exceeding 40-50 miles per hour [2]. Hawaii is no stranger to tropical systems, having been brushed by several in the past [3]. However, it is rare that a tropical cyclone makes landfall or directly impacts the Big Island [3]. Usually, the systems that do so tend to be relatively weak. A look at the sea surface temperatures around Hawaii can give us an idea why (see Figure 2):
Figure 2: Tropical Central Pacific sea surface temperature chart for July 15, 2023, as Hurricane Calvin was on approach to Hawaii. Figure borrowed from https://www.tropicaltidbits.com/analysis/ocean/.
Most tropical cyclones that impact Hawaii and the Big Island tend to approach from the east [3]. As Figure 2 shows, sea surface temperatures to the east of the island are in the 22-to-25-degree Celsius range [4]. In general, most tropical cyclones require sea surface temperatures of 26 degrees or higher to sustain deep convection and thunderstorms [5]. Thus, it makes sense that Calvin would weaken significantly on approach to the island.
Furthermore, the sea surface temperatures in the tropical Central Pacific Ocean are running below normal for this time of year (Figure 3), with some areas seeing SSTs running as much 1 to 2 degrees Celsius below normal [4]. This means there is even less oceanic heat content available than usual to fuel Calvin on its approach to Hawaii. The cooler-than-normal water in the tropical Central Pacific is in stark contrast to the El Niño strengthening to the south along the equatorial central and eastern Pacific [6]. If significant enough, this “cold pool” in the central Pacific could dampen overall tropical cyclone activity in the central Pacific this year despite the ongoing El Niño and otherwise favorable conditions. This is obviously good news for the island of Hawaii, and the impacts from Calvin are expected to be minimal.
Figure 3: Sea surface temperature anomalies for the central tropical Pacific Ocean around Hawaii. Cool colors indicate SSTs below the historical average, while warmer colors indicate warmer-than-normal SSTs for this time of year. Figure borrowed from https://www.tropicaltidbits.com/analysis/ocean/.
Elsewhere, Typhoon Talim continues to churn in the South China Sea, with a landfall in the Guangdong province of China imminent [7]. The storm already impacted Hong Kong over the weekend, bringing gusty winds and heavy rainfall [8]. The latest graphic for Talim, as displayed in KinetiCastTM, is shown below:
Figure 4: Projected wind swath of Typhoon Talim, generated by KinetiCast™ models using forecast data from the Joint Typhoon Warning Center (JTWC). The filled in circles represent the past/forecast path of the cyclone color-coded by intensity.
Currently, the total losses from Talim as shown on KinetiCastTM are estimated at 1.416 billion US$ in Purchasing Power Parity (PPP). PPP is used to allow for quick comparisons between countries of different economic levels. The good news for China is Talim is quickly running out of time to organize further; however, even a category 1-equivalent typhoon can cause major impacts from strong winds that can easily damage structures as well as rainfall-induced flooding and coastal storm surge [7].
We are quickly approaching the peak of the Northern Hemisphere tropical cyclone season. Here at Kinetic Analysis Corporation, we provide you with accurate, near real-time information about a tropical cyclone as it unfolds. We do this by synthesizing information from a variety of sources and translating the meteorological hazards into easily digestible impacts information. This includes populations affected by tropical storm/hurricane force winds and storm surge, economic loss and structural damage estimates, and shutdown times for facilities such as airports and seaports. All of this information is available in our state-of-the-art web app, KinetiCastTM. Now for a limited time, we are providing the first six months free for the first 20 people who sign up to use our web app. If you would like more information, please reach out to aagastra@kinanco.com.
References
1. https://www.nhc.noaa.gov/?epac
2. https://weather.com/storms/hurricane/news/2023-07-14-hurricane-tropical-storm-calvin-hawaii
3. https://weather.com/storms/hurricane/news/2022-07-12-hawaii-hurricanes-tropical-storms-history
4. https://www.tropicaltidbits.com/analysis/ocean/
5. https://www.weather.gov/source/zhu/ZHU_Training_Page/tropical_stuff/hurricane_anatomy/hurricane_anatomy.html#:~:text=The%20first%20condition%20is%20that,over%20water%20below%20this%20threshold.
6. https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/
7. https://www.nationalheraldindia.com/international/south-china-on-guard-as-typhoon-talim-nears
8. https://www.scmp.com/news/hong-kong/health-environment/article/3227874/hong-kong-raises-no-3-typhoon-warning-signal-tropical-storm-talim-intensifies