National Weather Summary for Friday July 17, 2009
NATIONAL WEATHER SUMMARY:
Across the East, a cold front moved across the northeast states during the day. Thunderstorms began forming during the midday hours across central New York and quickly became severe as they moved across eastern New York as well as portions of far eastern
Pennsylvania, New Jersey and the western New England states. Dime-
to quarter-size hail along with gusty winds was reported across
this area, including Philadelphia, where numerous trees were
reported down across the city. Warm and muggy conditions ruled the
Southeast with most areas from Virginia to the Gulf coast had highs
in the 90s. The moisture laden air aided in numerous thunderstorms
across the Gulf coast states and into the Carolinas during the day.
Heavy downpours accompanied a lot of the thunderstorms, especially
across Mississippi and Alabama. Severe storms were limited across
the Southeast but there were a few reports of wind damage with
afternoon storms across the central Carolinas.
Over the Central US, unseasonably cool weather overtook the Dakotas and Upper Midwest. Temperatures averaged 10-15 degrees below normal across the region making it feel more like September. New records for coldest highs for the date were set at Watertown, South Dakota (67) and St. Cloud, Minnesota (66). Meanwhile across the south, very hot weather continued with highs exceeding 100 degrees again over most of Texas and southern Oklahoma as well as portions of southern Arkansas and northern Louisiana. In between these two air masses, scattered to numerous thunderstorms occurred throughout the day. One complex moved southeast from eastern Nebraska and Kansas to southern Missouri by the afternoon hours. Strong to severe thunderstorms erupted during the afternoon hours in a large area from the Texas panhandle through central and southern Oklahoma and southern Arkansas. Over 100 severe storms containing large hail and winds to 60 mph and greater were reported here through Thursday evening. Additional strong to severe storm were developing across Illinois and Indiana during the evening hours.
The West was the quiet region during the day Thursday. Scattered thunderstorms were experienced across portions of New Mexico, Arizona and southeast California but the remainder of the region was high and dry as a large ridge of high pressure was in place.
Above normal temperatures dominated the region with highs easily
eclipsing 100 across the Desert Southwest and California Valley
areas. A record high temperature of 83 was set at the Seattle
weather service with even warmer temperatures across the rest of
the Seattle area.
NATIONAL EXTREMES YESTERDAY:
HIGHEST TEMPERATURE (DEGREES F)............125 Death Valley, CA
HIGHEST HEAT INDEX (DEGREES F).............125 Death Valley, CA
LOWEST TEMPERATURE (DEGREES F)..............33 Stanley, ID
LOWEST WIND CHILL (DEGREES F)...............33 Stanley, ID
HIGHEST WIND GUST (MPH).....................72 Tinker AFB, OK
HIGHEST PRECIPITATION (INCHES)............2.79 Dothan, AL
ON THIS DATE IN HISTORY:
In 1934, today would mark the beginning of one of the worst heat waves in U.S. history. Extreme heat during the last two months of July would kill 679 people in Michigan, 300 of which would be in Detroit.
In 1987, tragedy struck the area west of Comfort, Texas as torrential rains brought rising floodwaters from the Guadalupe
River. A church bus carrying 43 people was swept into the raging
river; 10 people perished.
In 1997, Tropical Storm Danny strengthened off the Louisiana coast and would eventually stall over Mobile Bay and dump very heavy rain along the Alabama coast. Danny was the fourth storm of the season, only the third time that four storms had formed so
DTN/Meteorlogix: J Sullivan