July 2010 Climate and Hydrology Highlights

July 2010

Tulsa: June 2010 was 30th warmest (84.4°F, tied with 1999 and 1993, since 1905) and the 29th wettest (4.67", since 1888) July on record.

Tulsa: July 2010 ranked 7th for warmest monthly average minimum temperature (since records began in 1905).

Tulsa: A daily rainall record was this month: 2.48" on 7/08/2010 (previous record was 1.02" in 1906)

Fort Smith: July 2010 was the 19th warmest (84.4°F, tied with 1966 and 1884) and 63rd driest (2.47", tied with 1975) July since records began in 1882.

Fort Smith: July 2010 ranked 2nd for warmest monthly average minimum temperature (since records began in 1882).

Record warm minimum temperatures and record cool maximum temperatures were set at McAlester and Fayetteville this month. Daily rainall records were set at Tulsa and McAlester.

Fort Smith had 4 days in a row with minimum temperatures >= 78°F, which ties for the 9th greatest number of consecutive days at or above this temperature. Tulsa also tied for 9th greatest number of consecutive days at or above 78°F, with 6 days in a row. July 1, 2010 was the only day during the month where the daily low temperature was below 70°F at both Tulsa and Fort Smith.

This month, moderate flooding occurred along the Neosho River near Commerce. Minor flooding occurred twice this month along the Illinois River near Watts and along the Caney River at Bartlesville. Luckily, the minor flooding was short-lived near Watts and in Bartlesville.

According to the Oklahoma Climatological Survey (OCS), southeast OK ranked as the 15th driest warm growing season (March 1 - July 31) since records began in 1921.

Rainfall totals for July 2010 primarily ranged from 2 to 6 inches across eastern OK and northwest AR. However, there were pockets of only 1 to 2 inch totals, as well as areas which received around 10 inches of rain this month.

Washington Co. AR received a locallized rainfall maximum (highest totals in the area this month) while immediately to the west, Adair and Cherokee Counties were in a locallized minimum of rainfall (receiving some of the lowest rainfall totals this month). The rainfall at Fayetteville exceeded 9 inches this month (most of which fell on the 13th and 15th). Another example illustrating the localized nature of this month's rainfall shows up across the Tulsa Metro Area, where Jenks Riverside Airport (RVS) received a total of 8.63 inches of rain this July, while approximately 12 miles away, the Tulsa International Airport (TUL) received 4.67 inches.

The Climate Prediction Center (CPC) outlook for August 2010 (issued July 31, 2010) indicates a slightly enhanced chance for above average temperatures and an equal chance for above, near, and below median precipitation. For the 3-month period Aug-Sep-Oct 2010, CPC is also forecasting a slightly enhanced chance for above average temperatures and an equal chance for above, near, and below median precipitation (outlook issued July 15, 2010). The enhanced chance for above normal temperatures is consistant with a developing La Niña.

Sea-surface temperatures in the equatorial Pacific have continued to decreased and are now La Niña conditions are present. CPC, has issued an La Niña Advisory and La Niña conditions are expected to strengthen and last through the Northern Hemisphere winter 2010-11.

According to the Drought Monitor on July 27, 2010, abnormally dry (D0) and moderate drought (D1) conditions existed across Choctaw, Pushmataha, and southern Le Flore Counties in southeast Oklahoma. No drought conditions existed elsewhere across eastern OK or northwest AR.