U.S. Drought Monitor Report for the Week Ending March 12 (Text)

Following is the text of the weekly U.S. Drought Monitor as released by the National Drought Mitigation Center in Lincoln, Nebraska:

Weather Summary: The past week featured two major storm systems.
The first was a deep low-pressure system that impacted portions
of the contiguous 48 states from the Mid-Atlantic to the
Northeast, producing moderate rains over the Mid-Atlantic (0.5 -
1.5 inches).  As the storm lingered near the northeast, it
produced significant rains (0.5 - 3.0 inches) and snows
(scattered reports of greater than 6 inches with isolated
reports of more than 1 foot) for New England.  Later in the
week, a storm system entered the west coast and brought heavy
precipitation (0.5 - 4.0 inches) to northern California and the
southwest.  During the weekend, the focus of precipitation
shifted to the central and eastern portions of the contiguous 48
states, with wide swaths of precipitation falling across the
central Great Plains and Midwest.  The wet weather moved toward
the east coast toward the end of the weekly analysis period. A
wet pattern (0.5 - 6.34 inches of precipitation) continued
across southern Alaska. Most stations on Puerto Rico reported at
least some precipitation, except for the majority of stations
near the northwest portions of the island.

The Northeast and Mid-Atlantic: Generally 0.5 to 1.0 inches fell
on the D0 areas, but the precipitation was not enough to change
the intensity or coverage of the dry areas substantially for the
northeast.  Moderate rains (0.5-2.0 inches) fell across central
Virginia, prompting the removal of the D0 (abnormal dryness) in
this region.

The Southeast: Light to moderate rains (0.5 - 4.5 inches) fell
across the Tennessee Valley, with lighter amounts across
Alabama, Georgia, and the Carolinas (0.5 - 2.0 inches).  Some
improvement was made across eastern Alabama and north Central
Georgia as the rains were slightly above-normal for the week,
and continued the recent wet period over the past 90 days (110-
120 percent of normal precipitation), as indicated by the
Advanced Hydrologic Prediction System (AHPS) precipitation
analysis.

Dry conditions continued across Florida, prompting the expansion
of D1 across Collier, Glades, and Charlotte Counties.  Keetch-
Byram Drought Index (KBDI) values and low water levels in Big
Cypress National Preserve support the latest depiction, with
burn bans being the latest impact to emerge.  Severe drought
(D2) was expanded over Lake County as well.

The drought depiction across the Carolinas was left unchanged as
the light rains that fell were not enough to warrant changes to
the depiction.  Some streamflows have not responded to the
recent (90-day) wet period.

The Midwest: Light precipitation (0.5 - 1.5) inches fell across
Michigan and Indiana, so the area of abnormal dryness (D0) was
trimmed slightly.  Areas with above-normal rainfall over the
past 30-days were targeted for improvement, but some D0 was
retained due to longer term soil moisture deficits that reflect
long-term drought reaching back to last summer.

Despite significant rains (0.5 - 3.0 inches), only minor
improvements were also pursued over Illinois, Wisconsin, and
Minnesota.  According to some local National Weather Service
employees and state climatologists, the frozen ground (10-20
inches of frozen soils) is preventing deep soil moisture
recharge.  Streams and rivers rose and fell rapidly, indicting
excessive runoff and lack of penetration, along with some
reports of basement flooding as the water cannot go into the
soil.

A nearly 1-category improvement across Missouri and Iowa was
prompted by widespread rains (0.5 - 2.5 inches).  The
improvements were not a full 1-category as some areas of
northwest and north-central Missouri did not experience as
significant of a soil moisture recovery as points farther east
and south, where soils had thawed earlier in the year.

The Great Plains: Farther north and west, some improvements were
made across south-central and southeast South Dakota due to
recent rains (0.5 - 1.5 inches).  Excessive drought (D4)
conditions were removed from south-central South Dakota and
extreme Northern Nebraska.  Drought conditions intensified
across northwestern South Dakota, so extreme drought (D3) was
expanded to the northwestern portions of the state.  Across
Nebraska, recent surveys by the state climatologist and soil
moisture measurements prompted from reassessment of conditions,
resulting in a slightly different depiction of the D4 area.

Improvements were also pursued across Kansas and Oklahoma due to
widespread rains (0.5 - 4.6 inches).  The heaviest rains fell
across southeast Oklahoma, so the most improvement was pursued
there.  The coverage of D3 was reduced across east-central and
south-central Kansas, and western Oklahoma.  Despite only modest
rainfall this week, lower temperatures and a slightly wetter
pattern over the past couple of months prompted a trimming of
the exceptional drought over Texas County in the Oklahoma
panhandle.

A reduction in the covered of severe drought (D2) was included
as beneficial rains (0.5 - 1.6 inches) fell on the panhandle of
Texas.  Over central Texas, high winds and low-relative humidity
values negated any benefits from the rains that fell this week.
Most of the rest of Texas experienced dry weather, prompting
minor expansions of D4 over southern Texas, and severe drought
over eastern portions of the state.

The Rockies: Winter storms brought precipitation to the
southwest, prompting the removal of some dryness near central
Arizona, specifically near Gila County.  Rains there exceeded
2.0 inches for a few reporting locations.  The same storm system
brought some snows to higher terrain of Arizona, but not enough
to significantly increase the surface water supply forecast or
the reservoir storage.   Nevada and New Mexico are also
experiencing very low reservoir levels, so the current
depiction, which contains significant amounts of extreme
drought, seems accurate.

Areas of central Utah have fared slightly better this winter,
with some SNOTEL stations reporting near median snow water
equivalent (SWE) values.  The latest Water Supply Forecast
Summary from the USDA-NRCS indicates Utah has above-average
reservoir storage.  Those two factors contributed to a removal
of D2 across the Sevier River Basin.

The storm system that moved across the west brought significant
precipitation to much of California, with isolated reports in
excess of 2.0 inches across southern California and much higher
amounts across northern California and the Central Sierras (over
10 inches at a couple of stations).  This prompted some removal
of D0 (abnormal dryness) across northern California, and a
slight trimming of D1 conditions across southern California.

Hawaii, Alaska, and Puerto Rico: Improving conditions were
reflected in the drought depiction over Molokai, where rainfall
over the past several weeks has improved vegetation conditions,
according to reports from COOP observers in west Molokai.
Reports indicated that saying grasses are coming back in the
area.  This is consistent with rainfall data and satellite based
VHI data.  The D3 area on Maui was reduced by trimming off the
eastern portion and replacing with D2.  FSA reports indicated
that pastures from Ulupalakua to Kaupo have improved.  The Kihei
and lower Kula areas are still in bad shape and ranchers have
been leaving pastures unused.  Persistent dryness prompted an
intensification of the drought on the big island.

Heavy precipitation fell across many parts of the Alaskan
Panhandle and south-central Alaska near the Kenai Peninsula, so
the area of D0 was trimmed out.  Dry conditions persisted across
interior Alaska and around the Norton Sound-Seward Peninsula, so
D0 was expanded across that region.  D) was expanded across
portions of the Koyukuk and Kuparik Basins to reflect the
abnormally low snowpack and low SWE (less than 80 percent of
normal), while it was trimmed from portions of the Yukon River
Valley to reflect more robust snowpack levels.

Light to moderate rains fell across Puerto Rico, with the
exception of dry conditions across the northwest sections of the
island.  No change was made in the depiction.

Looking Ahead:  During the next 5 days (March 14-18, 2013),
moderate to heavy precipitation is forecast for the Pacific
Northwest, northern Rockies, Great Lakes, and Ohio Valley.
Outside of those regions, little to no precipitation is
expected.  Much colder than normal temperatures are likely to
support a continuation of the frozen soil problem across the
northern Great Plains through the next week, while the Rockies
and southern Great Plains are expected to experience warmer than
average conditions.  Colder than normal conditions are likely to
persist through the next 10 days from California to the northern
Great Plains to the Northeast, with the most likely locations
for above-normal temperatures are across the southeast.  Wet
conditions are likely to continue for the Great Lakes, northern
Great Plains and southeast, with drier than average conditions
likely across the southwest.

To contact the reporter on this story: Stephen Rose in Washington at srose31@bloomberg.net

To contact the editor responsible for this story: Marco Babic at mbabic@bloomberg.net

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