Saturday, August 02, 2008
(Last modified: 2008-08-02 00:43:35)
 

Source: The Greeneville Sun

Weather Service:

Rainfall Less Than

70% Of Normal

By BILL JONES

Staff Writer

The National Weather Service reports that drought conditions had "deepened" as of July 26 in most of Greene County and adjacent counties.

"Extreme drought conditions persisted, as of July 26, in the mountainous and foothill portions of Tennessee's Greene, Cocke, Polk, Monroe, Blount, Sevier, Unicoi and Carter Counties," according to the National Weather Service (NWS) office in Morristown.

A spokesperson there said on Friday evening that those drought conditions have persisted in this county throughout the past week, despite some rain.

The NWS meteorologist said Greene County currently has a D3 rating, which signifies an "extreme" drought. He said the only worse rating would be D4, which would for an "exceptional" drought.

Extreme drought conditions also persist in North Carolina's Cherokee County and the western half of Clay County, according to the weather service Web site.

The weather service also notes that for the period from Jan. 1, 2007, through midnight Friday, July 26, 2008, the official weather monitoring stations nearest Greene County had recorded rainfall totals of less than 70 percent of normal.

On Friday, the University of Tennessee Research & Education Center on East Allens Bridge Road reported a total of 0.39 inches of rainfall since July 26.

This amount includes 0.32 inches of rain on July 31, according to a spokesman at the center.

At Tri-Cities Regional Airport, according to the weather service, 43.57 inches of precipitation (65 percent of normal) had been recorded against an average of 67.20 inches for the period over the years. That left a deficit of 23.63 inches.

At the Weather Service office in Morristown, 50.82 inches of precipitation (69-percent of normal) had been recorded as opposed to an average rainfall total of 73.79 inches for the period. That left a rainfall deficit of 22.97 inches.

But rainfall totals over large areas such as reservoir drainage basins are a much better indicator of an area's "rain health" than simple point totals, according to the weather service.

Rainfall data for the Tennessee Valley Authority reservoir basins in the Upper Tennessee River drainage for the period of Jan. 1, 2007, through 6 a.m. Saturday, July 26, indicate that the Cherokee Lake basin, which includes Greene County, also has experienced a rainfall deficit.

Specifically, the Cherokee Reservoir Basin received 51.03 inches of precipitation (73 percent of normal) against an average of 69.93 inches over the years. That left a deficit of 18.90 inches.

No widespread serious local or regional water supply, fire, navigation, or recreational impacts related to drought conditions are known, although some water districts in the region are on either mandatory or voluntary restrictions, according to the weather service.

"Some small springs and wells are still lower than normal around the region, which (can) affect local or individual water supplies," the weather service reports.

Stream Levels Drop

During July, streams in the region have experienced a general drop in water volume due to sporadic rains for the season.

"Some places have received no rain in the last week," the Web site says. "Small streams are generally in the bottom 10 percent of streamflow for the date in history. A few, especially those flowing out of the mountains and on the Cumberland Plateau, are at record low levels for the date."

Runoff for 2008 so far for the Upper Tennessee River Basin was only 52-percent of normal, according to the Web site. "This means the ground is so dry that it is sucking up much more of the rain that falls than is normal," the Web site says. "Reservoirs are lower than normal."

Precipitation Outlook

The weather service Web site also spells out the precipitation outlook for August through October.

"Through about Aug. 3, general conditions are expected to be near normal for the region as a whole, with temperatures on the slightly cool side," the weather service Web site says. "Individual locations may vary. However, there is a slight chance for some rain each day. As is the usual case with summertime rain, some places will get it and some will not."

TheAug. 3-7 period "is expected to a little cooler and wetter than normal, overall," the Web site notes.

For the rest of August through October, climate outlooks are for close to normal for both temperature and rainfall, according to the Web site.

"The ramification of this outlook are that slightly lower than normal [evaporation] is expected," the NWS Web site says. "This means a potential slight wetting of the soils, and less stress on plants. The forecast is for the drought to persist, though some improvement may be in store for some areas of East Tennessee, extreme Southwest Virginia, and Cherokee and Clay counties in North Carolina."

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