May 4 Biggest Severe Weather Day of Season So Far

Just-ended U.S. Cool Season Gas Population Weight HDD Anomalies
05/03/2021, 8:34 am EDT
Harsh North Dakota Drought To Last
06/04/2021, 5:13 am EDT
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Fig. 1-2: Severe weather reports for yesterday and today’s severe weather outlook.

Severe weather discussion: On Tuesday NOAA/SPC issued 495 severe weather reports, mostly damaging wind gusts (Fig. 1). The amount was slightly higher than the previous high amount for 2021 (480 reports on April 9). The 2-day total for severe weather reports is a whopping 922! The Virginia severe weather was buoyant and not in the morning NOAA/SPC Outlook for severe weather. Today the thunderstorm activity shifts ease and loses intensity (Fig. 2). One exception is the Florida Panhandle to southern Georgia where severe storms erupt.

Soil moisture/rainfall outlook discussion: A significant predictor of climate is the regional soil moisture regime once we’re into the warm season. The soil moisture regime is a reflection of the long-term climate. In April 2021, the U.S. soil moisture regime revealed widespread dryness across the western half of the U.S. and the northern Ohio Valley to northern New England while elsewhere soil moisture was normal or wetter than normal (Fig. 3). The 15-day ECM ENS percent of normal rainfall forecast indicates most areas in the U.S. without dry soils are wetter than normal (Fig. 4). The forecast is trending wetter!

Fig. 3-4: The April 2021 U.S. soil moisture anomalies and ECM ENS 15-day percent of normal precipitation forecast.

U.S. population-weight CDD outlook: Cooling demand trends farther below normal for next week compared to 24 hours ago (Fig. 5).

Fig. 5: U.S. population weight cooling degree day forecast for the U.S. compared to 30-year and 10-year normal.