Another Record Hot Month for The West Coast in July

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California and the rest of the West Coast plus Nevada observed their hottest July on record. Meanwhile, New York and Massachusetts observed their wettest July on record. Overall, the U.S. ranked 6th wettest and 13th warmest given the 127 year climatology in July.

Fig. 1: NOAA state average temperature ranks for July 2021.

Discussion: Extremes rule once again during mid-summer! The entire West Coast plus Nevada observed their hottest July on record (Fig. 1). Arizona and New Mexico were not as hot due to the Southwest U.S. Wet Monsoon although to the north, The Great Basin and central/north Continental Divide States were all in the top ten hottest rankings. The North-central U.S. was hot as drought continued in that region. North Dakota observed their 3rd hottest July. The Mid-Atlantic States and Florida were warmer than normal. The cooler spots were also plentiful mostly due to clouds/showers. Heat was suppressed in Texas to the Missouri Valley and parts of the Southeast States plus northern New England.

New York State and Massachusetts observed their wettest mid-summer on record (Fig. 2). The entire Northeast was much wetter than normal. Most of the southern half of the U.S. plus the Ohio Valley were wetter than normal. Many southern states were close to record wet including Mississippi, Texas and Arizona. Only the far northern states from Washington to Mississippi were dry all ranking in the top 13 driest in the 127-year climatology.

Interestingly, the wet mid-summer signature is characteristics of a climate pattern associated with a cooler than normal North Atlantic basin. The basin average was slightly warmer than normal in July but somewhat cooler than the 20-year average.

Fig. 2: NOAA state average precipitation ranks for July 2021.