NATIONAL WEATHER SUMMARY

APRIL 2011

1st-4th…The main weather story was over the East Coast Tuesday as a
strong cold front pounded through the region. Thunderstorms with light
to moderate rain fell from Florida to the Mid-Atlantic and a mix of
snow and rain developed from northern Mid-Atlantic and Central
Appalachians up to Maine. In particular, severe weather occurred over
portions of the Mid-Atlantic and Florida with hail and damaging winds.
Some trees and power lines were blown down and blocked roadways. Apart
from the precipitation, much colder air swept through the Eastern U.S.
Tuesday in the wake of the cold front. Winds became west and northwest
which caused temperatures to plunged. Temperatures had dropped 15 to
25 degrees since midday.
Moving to the West, a Pacific system pushed farther inland Tuesday and
brought more rain and mountain snow from the Pacific Northwest
eastward across the Intermountain West, Rockies and Northern Plains.
In addition, winds increased to 25 to 40 mph in the afternoon along
and behind the cold front. Elsewhere, warm and dry weather prevailed
across much of the South and Southwest Tuesday as high pressure held
in place. Temperatures climbed well into the 80s with a few low 90s in
the afternoon.

10th-16th…Low pressure in the Mid-Atlantic brought precipitation and
strong thunderstorms to the country from central Florida through
Eastern Massachusetts. Heavy rain also fell in the central
Appalachians. Western Pennsylvania and West Virginia both saw heavy
rain throughout the day. While strong thunderstorms were reported
throughout the region, no damage had been reported by late afternoon.
A cold front that dropped through the northern Rockies and Plains
brought some cloud cover and showers to the Rockies and Dakotas, but
no significant precipitation was noted outside of the mountains where
some snow fell on the peaks. In the Great Basin, showers were reported
through eastern Nevada and western Utah.
On the West Coast, Sunny skies were reported from border to border,
though a few patches of fog remained from the morning hours across the
Oregon coast. The Northeast saw more rain showers on Wednesday, while
wet weather returned to the Pacific Northwest. A low pressure system
in the Northeast slowly moved offshore, allowing for scattered showers
to end across much of New England, but periods of heavy rain persisted
over the extreme Northeast. Rainfall totals ranged from 1 to 2 inches
from Massachusetts to Maine, with 2.53 inches reported in
Provincetown, Massachusetts. Precipitation remained as rain across the
region as high temperatures ranged in the 40s and 50s. To the south, a
cold front produced by this low shoved eastward and off the East Coast
into the Atlantic Ocean. The tail end of this cold front stretched
into the Bahamas and the southern tip of Florida, where it triggered
more light and scattered rain showers. High pressure quickly built in
behind this front, which allowed for sunny skies and warm temperatures
to build over the Mississippi River and Southern US. Highs reached
into the 80s in the Southeast and into the 90s in parts of Texas. In
the Northern Plains, a weak trough of low pressure moved through the
Dakotas and into the Upper Midwest. This kicked up a few light
sprinkles. Meanwhile, Out West, a low pressure system moved onshore
from the Pacific Ocean and pushed a cold front onshore with it. This
front produced periods of heavy rain as it extended down the West
Coast, while the Pacific Northwest saw more continuous rain showers
throughout the day. Light snow developed at higher elevations of
Washington, Oregon, and Idaho.

17th-23rd…The low pressure system that brought a late winter storm to
parts of the Upper Midwest yesterday lifted across the Lower Great
Lakes Wednesday, bringing active weather to areas from the Upper Great
Lakes through parts of New England and the northern Mid-Atlantic. Wrap
around wind from this low combined with a colder airmass over the
Upper Great Lakes and produced bands of light rain and snow showers in
Wisconsin and northern Michigan. Meanwhile, an associated warm front
lifted through southern New England and sparked periods of light to
moderate rain showers in already saturated areas of New York, Vermont,
and New Hampshire and snow showers in northern Maine. Flood Watches
and Warnings remained in effect for parts of these states, while
Winter Storm Warnings and Winter Weather Advisories remained in effect
for northern Maine. To the south, scattered rain showers developed
ahead of the northern portion of an associated cold front in
Pennsylvania. The front extended southwestward through the Tennessee
Valley and into eastern Texas. Areas of rain and thunderstorms
developed ahead of this system in Arkansas, Alabama, and Mississippi.
A moist, warm, and unstable airmass ahead of this front created a
slight risk for severe weather development with damaging wind and hail
from parts of Texas through the Gulf Coast States. Thus far, numerous
quarter to golf ball sized hail (1.00 to 1.75 inches in diameter)
events were reported in Arkansas and Mississippi. Damaging wind events
were also reported in northern Alabama and northern Georgia with tree,
home, and powerline damages. Elsewhere in the nation, moist flow
streamed across the West Coast today and kicked up a few scattered
showers and high elevation snow showers in parts of Oregon and
California. Elsewhere, a few light showers, mainly sprinkles,
developed in the Central Great Basin.

24th-30th…Severe storms popped up across the southern Plains and Lower
Mississippi River Valley on Monday. The system obtained energy as flow
around it pulled in moisture in from the Gulf of Mexico. This produced
warm and humid conditions along a front that triggered heavy showers
and thunderstorms from the Great Lakes to Texas. Warmer and more humid
conditions in the South allowed for these storms to turn severe.
Nickel to quarter size hail was reported in Wylie and Garland, Texas,
with winds estimated at 45 to 55 mph. Meanwhile, multiple trees and
power lines were blown down by strong wind gusts across Arkansas and
Oklahoma. The system even produced tornadoes, with multiple tornadoes
spotted across Shelby county in Tennessee. Rainfall totals varied
between 1 to 2 inches, with up to 3 inches in areas of severe
thunderstorm activity. Coffeyville, Kansas reported a mid-day total of
3.10 inches of rain. The northern side of this system brought lighter
rainfall and less intense winds to the Midwest and up the Ohio River
Valley as the system extended toward the Northeast. Rainfall totals
ranged around a half of an inch across the Midwest, with winds around
20 mph. In the West, more rain showers developed as a low pressure
system and associated cold front moved over the Pacific Northwest.
This created widespread scattered showers with periods of strong winds
across Oregon, Washington, and northern California. Tillamook, Oregon
reported 0.84 inches of rain and Crescent City, California reported
wind gusts up to 36 mph.