Extreme Rains Over Southern Florida This Week

Fig. 1: Tracking U.S. population weight CDD forecasts for summer 2024.

Discussion: The U.S. summertime CDD forecasts are trending warmer of late close to the “hottest” forecast previously issued on April 25. The forecast trend indicates the April 25 values will be exceeded in subsequent outlooks. The latest forecast brings the summer 2024 monthly CDD projection to near or above the 10-year normal for each month of meteorological summer (Fig. 1).

The NOAA/WPC 5-day rainfall forecast indicates up to 20 inches of rain across southwest Florida (Fig. 2). The heavy rain is caused by a fetch of tropical moisture across Florida to the south of a stationary frontal system across Northern Florida. In the 6-7-day period the rainfall area shifts westward to the northeastern Gulf of Mexico with a chance of some tropical development (Fig. 3).

The latest NOAA/NWS weather watch, warning, and advisory areas across the U.S. remain focused on a heatwave in California and the Southwest U.S. and flooding in the Mid-south States (Fig. 4). The Excessive Heat Warning across the Northern San Juaquin Valley is in effect through Wednesday. A Heat Advisory extends to the northern and eastern SFO Bay Area. The Excessive Heat Warning in the Phoenix area is due to maximum temperature forecasts of 110F for tomorrow through Thursday. River flooding is widespread across Eastern Texas, the Lower Missouri Valley, and parts of the Upper Midwest (Fig. 5).

Fig. 2-3: NOAA/WPC 5-day and 6-7-day quantitative precipitation forecasts.

Fig. 4: NOAA/NWS weather watch, warning, and advisory areas.

Fig. 5: NOAA/USGS river gauge observations.

The latest U.S. population weight CDD forecast reveals slight changes from 24 hours ago and beginning next week is somewhat warmer than both the 10-year and 30-year normal (Fig. 6).

Fig. 6: The U.S. population weight CDD forecast utilizing all models, their consensus, and comparing with 24 hours ago and the 10-year/30-year normal.