Drought Monitor - Week Of 4 September 2007

[hatrack]

The West: Heat was the big story this week, as record-breaking triple digit temperatures seared California and other states, resulting in weekly readings averaging 4 to 8 degrees F above normal throughout the West, the only exception being parts of the Pacific Northwest. A few thunderstorms struck California, Arizona, and other scattered areas, but the moisture was generally not enough to offset the evaporation caused by the extreme temperatures. As a result, there was little change to the drought picture across the region.

The Plains and Midwest: Heavy showers extended from southeastern Nebraska into Wisconsin, but most of the rains fell outside of ongoing dry areas, so there was minimal change to the existing severe to extreme drought situation over northern parts of Minnesota, Wisconsin, and Michigan. Mainly dry weather in the Ohio Valley allowed drought to creep northward in southern portions of Illinois, Indiana, and Ohio.

The Southeast: A lingering cold front helped to focus widespread shower activity across the southeastern drought region, resulting in improvement over many areas. Temperatures also turned more seasonable following the previous week’s record heat, although weekly average temperatures remained at least 4 degrees F above normal in Tennessee and Kentucky, where rainfall was spotty and improvement was minimal. Amounts of 1 to 2 inches, with locally over 3 inches, spread from Mississippi into Alabama and Georgia, resulting in shrinkage of D3 and D4 drought. Weekly average streamflows, responding to recent downpours, neared median levels at many locations in northern and western Alabama. In Mississippi, topsoil moisture ratings improved from 76 percent short or worse to 59 percent short in the past week. Very heavy rains exceeding 4 inches eliminated dryness in southeastern Georgia, where statewide topsoil ratings improved from 75 to 55 percent short. Beneficial rains of 1 to 2 inches or more also covered much of Florida, improving soil moisture, although water supply impacts continued due to remaining substantial long-term rainfall deficits. In contrast, hot, dry weather caused D3 drought to extend eastward across much of North Carolina.

The Mid-Atlantic and Northeast: A return to drier weather resulted in declining streamflows over Maryland and northern Virginia, leading to slight expansion of D1 drought. Continued dry weather caused D2 to develop in upstate New York along the southern shores of Lake Ontario. Persistent dry weather resulted in reduced soil moisture and streamflows in Rhode Island and eastern Massachusetts, leading to D1 drought development. Boston has measured just 0.66 inches of rain since August 1, and a mere 0.01 inches since August 19.

Alaska, Hawaii, and Puerto Rico: Scattered showers failed to reduce drought in parts of Hawaii, while widespread rains further eased dryness in Puerto Rico, although D0 remained where long-term deficits persisted in the southeast. Rainfall was generally light in the D0 area of Alaska.
Looking Ahead: Weather events that could affect dry areas over the next 2 weeks include: 1) the potential for heavy rains of 1-3 inches or more on September 8-10 along the East Coast from the Carolinas to southern New England, as a tropical storm possibly develops off the Southeast coast and heads northward from the Carolinas; 2) heavy rains of 1-3 inches on September 5-8 across Arkansas, Missouri, and Illinois; 3) heavy rains September 8-9 over Minnesota; 4) mainly dry weather and above-normal temperatures across the far West, the remnant rains from Hurricane Henriette falling mainly east of Arizona’s drought areas.

Author: Thomas Heddinghaus, Climate Prediction Center

Dryness Categories

D0 ... Abnormally Dry ... used for areas showing dryness but not yet in drought, or for areas recovering from drought.

Drought Intensity Categories
D1 ... Moderate Drought
D2 ... Severe Drought
D3 ... Extreme Drought
D4 ... Exceptional Drought

Drought or Dryness Types
A ... Agricultural
H ... Hydrological



Updated September 5, 2007

[Dead_Parrot]

1. Nice

Does anyone have 1,395 km³ of BBQ sauce and a bun the size of India?

Oh, and some onion rings, if you've got 'em.

[Colorado Progressive]

2. Wow.I dont remember hearing of a drought like that in the south....

I think global warming is just screwing with weather everywhere. We have been soaked in the mtns this year, normally we are the ones red on the map.

[cliss]

3. Thank you for the article, hatrack.

As always, very good reading material, even though the topic is....dry....just kidding!

Horrific, actually.

[Missy M]

4. I'm in a severe drought area....

and we finally had some rain yesterday. Not alot but it helped some. Today looks like a sunny day and no rain. Our ground is so hard and the cracks in the ground are big. I can't remember going through a whole summer with little to no rain in our area.