July 2024 - Climate Impact Company

07/31/2024, 11:13 am EDT

Mid-South U.S. Flash Drought Followed by Some Relief After 10 Days

Extreme heat and, according to GFS, up to 240 hours with no rain in Arkansas (and vicinity) expect flash drought to develop in the Mid-South U.S. during early August. Some much-needed wet weather may generate in the 11-15-day period to bring slight relief.

07/31/2024, 8:36 am EDT

ECM Ensemble Best Medium-range Temperature Forecast Model for U.S. Past 30 Days; AIFS 4th Best

During the past 30 days (July), the 2-meter temperature prediction verification for North America is best forecast by ECM ENS while the volatile GFS is last. The Artificial Intelligence Forecast System (AIFS) was 4th of 5 leading models.

07/30/2024, 8:08 am EDT

Midwest U.S. Derecho Alert for Today

NOAA/SPC indicates risk of damaging wind due to severe thunderstorms from Des Moines to Nashville today. The HRRR model specifically defines the threat area beginning early afternoon on the southeast Iowa/northeast Missouri state line. The line moves southeastward across western Illinois mid-afternoon to southern Illinois late afternoon and into southwest Indiana by early evening.

07/30/2024, 6:06 am EDT

Possible Hotter Mid-August East; More Damaging Wind Midwest. Searing Mid-south heatwave underway!

Widespread high impact weather to close July primarily centered on an excessive heat event centered on the Mid-south U.S. but forecast to expand through early August. Previously, the mid-August forecast was trending less hot. But overnight, another hot spike appeared in the East U.S. according to the GFS model.

07/29/2024, 7:36 pm EDT

Subsurface Equatorial Pacific Is Cooling As La Nina Development Has Restarted

La Nina development stalled during the past 10 weeks or so as the subsurface cool waters required to ignite cold ENSO lost half their April intensity. However, during the past 7-10 days, cooling has resumed indicating La Nina development has returned. The Nino34 SSTA has cooled to -0.13C and appears to be trending toward the -0.50C La Nina threshold based on the 30-day change of -0.55C.

07/26/2024, 6:33 am EDT

Surprises! Possible TC East of New Jersey Monday? Cooler Looking U.S. 11-15-day Outlook?

Beginning yesterday, forecast models indicated potential evolution of a tropical system east of New Jersey. Water temperatures support tropical development (81-82F). Additionally, a very hot 11-15-day forecast from recent days is suddenly cooler into the Midwest according to GFS and AIFS.

07/25/2024, 8:57 am EDT

Buoyant Mid-Troposphere Relative Humidity Promises Busy Season Ahead in North Atlantic Tropics

While Saharan Dust has suppressed tropical cyclone activity for much of July, the mid-troposphere is quite wet and supports a buoyant tropical cyclone season ahead once the Saharan Dust issue eases likely by the middle third of August.

07/24/2024, 6:10 am EDT

Dangerous U.S. Heatwave is Ahead!

The U.S. population weight CDD forecast explodes to well above normal August 2-8. The GFS is the hottest model, but all ensembles are trending hotter. Contributing to the increasing CDD during early August are hotter forecasts in the PJM-East sector.

07/23/2024, 4:31 pm EDT

Southeast Great Plains Drought Risk

Deep layer soil moisture deficits are generally the result of a long-term dry climate pattern. When long duration (7-10 days) hot and dry weather moves across these regions, quick evolving (flash) drought can generate. These conditions are possible in the southeast Great Plains including Eastern Kansas to Central Oklahoma during late JUL/early AUG.

07/22/2024, 3:05 pm EDT

Extreme Heat ALERT for Late July Great Plains!

The latest 12Z ECM and GFS 6-10-day temperature anomaly outlook is agreeable to developing extreme heat in the central Great Plains. High temperatures reach 100F-105F from the Dakotas to Oklahoma during the period. Using ECM, the peak day is day-10 which is July 31. The 12Z ECM ENS widens the impressive heatwave back into the West, still peaking in the Central U.S., and stretching to eastern North America.

07/22/2024, 11:24 am EDT

Neutral ENSO Continues, Some Cooling NW Coast of South America

The 2024 daily southern oscillation index (SOI) identifies the uncertainty of direction in ENSO phase. Recently, SOI has spiked highly negative albeit for brief periods. The negative phase is an indicator of an El Nino climate. Conversely, a strong positive spike occurred late JUN/early JUL which indicates a strong La Nina climate. The recent spikes are a new SOI character compared to weaker daily SOI observations of MAR/APR/MAY 2024.

07/21/2024, 9:28 am EDT

Northeast Pacific Marine Heatwave Helping to Propel Western U.S./Canada Heat

Regions of very warm ocean water known as marine heatwaves (MHW) are commonly linked to high pressure in the upper atmosphere which cause a dry and warmer than normal climate. MHW’s are present and quite strong off the U.S. West Coast and south of the Canadian Maritimes.