NATIONAL WEATHER SUMMARY
OCTOBER 2009
1st-10th…A
major low pressure system tracked through the Upper Midwest and into the Great
Lakes on Friday. The associated cold front was draped from the central Gulf
Coast through the Ohio Valley. Along the southern end of the front, morning rain
and strong thunderstorms moved through the Southeast. As the front moved
eastward, this precipitation waned as its main moisture source was cut off. The
northern end of the front ushered moderate precipitation into the Ohio Valley
and western New England. Closer to the low pressure center, scattered showers
fell in the Northern Plains and Upper Midwest, while breezy conditions were also
noted. Areas of freezing temperatures are possible in the Central Plains. A high
pressure system in the western portion of the country provided dry conditions
throughout the West. High fire danger was noted in the hills of Southern
California and Red Flag Warnings were posted. The Northeast rose into the 50s
and 60s, while the Southeast saw temperatures in the 60s and 70s. The Northern
Plains rose into the 40s and 50s, while the Northwest saw temperatures in the
50s and 60s.
The
first major snow storm hit the Rockies on Monday. A strong low pressure system
developed over the Intermountain West created a cold front that kicked up wintry
weather over the Western US. Most of the West saw cooler than usual conditions
with highs only reaching into the 50s and 60s along the coast. This system
pushed moisture well inland as it moved eastward overnight and triggered 2-4
feet on the north facing slopes of the Montana, with lighter accumulation,
between 1-2 inches over most of the Northern and Central Rockies, with periods
of heavy snowfall reported. A winter storm warning has been issued over the
region, as Billings, Montana reported 4 inches of snow on Monday. The leading
edge of this system stretched into the Plains, and also brought cool and wet
weather to the region. The Northern Plains saw highs in the 40s with a quarter
of inch of rain reported in Bismarck, North Dakota, and 1.19 inches of rain fell
over Pierre, South Dakota. Overnight lows dropped well into freezing over most
of the Northern Plains. The Central and Southern Plains remained dry on Monday
with increasingly cloudy and windy conditions with the incoming front. Kalvesta,
Kansas saw overcast skies and 28 mph winds with gusts up to 35 mph. Highs ranged
from the upper 50s to upper 60s in the South. In the East, pleasant fall weather
persisted over the Mississippi and Ohio River Valleys as a small ridge of high
pressure built in. However, in the Northeast, light and scattered showers
persisted as a large low pressure system hovered over eastern Canada. To the
South, a front lingered over the Gulf States and allowed for another day of
scattered showers and thunderstorms. Alma, Georgia reported 0.78 inches of rain.
Cold
and wet weather developed in the Upper Northwest on Wednesday as an Arctic cold
front dropped across the Northern Rockies. Strong winds and areas of light to
moderate snowfall accompanied the front and created periods of blowing snow and
hazardous driving conditions for travelers. As the front trekked southeastward,
a colder airmass began to pour in behind the system and yielded to colder
daytime temperatures. To the south, low pressure in the Southwest kicked up
pockets of light precipitation in the Four Corners. As this system shifted
eastward and the aforementioned cold front draped across the Northern Rockies,
scattered showers and thunderstorms developed in the Southern High Plains.
Meanwhile, Gulf moisture fueled rainfall and thunderstorms in western Oklahoma
and southwestern Kansas. Significant moisture and daytime heating heightened
instability in these regions and created a chance for strong thunderstorms with
hail, damaging winds and locally heavy rainfall. In the East, areas of scattered
showers and isolated thunderstorms developed from Texas through the Southeast.
To the north, a strong low pressure system produced very strong northwest winds
and precipitation across northern New England.
An
interesting mix of weather common for early Fall tracked through the country on
Friday. Most of this activity was produced by a long, slow-moving front that
began the day stretched from the Southern Plains through the Great Lakes. As the
day progressed, it moved eastward across the Mississippi Valley and into western
New England. A tremendous amount of moisture streamed along the front from the
Gulf of Mexico and produced widespread moderate to heavy rain through much of
the region it passed over. A few thunderstorms developed ahead of the front and
instigated Tornado Watches from Mississippi Valley through eastern Kentucky.
While these thunderstorms did not produce any tornadoes into the afternoon,
there were numerous reports of wind damage from Louisiana through Kentucky. Warm
air streamed into the Southeast and pushed temperatures well into the 80s and
90s. Meanwhile, a tongue of cold air plunged southward into the Intermountain
West and Northern Plains. This cold air greatly dampened daytime high
temperatures in the area. Some snow showers did develop in the western Plains.
The rest of the West remained dry ahead of a major storm that will slam into the
West Coast after the weekend. The Northeast rose into the 50s and 60s, while the
Southeast saw temperatures in the 80s and 90s. The Southern Plains rose into the
50s and 60s, while the Northwest saw temperatures in the 50s and 60s.
11th-17th…Wet
and unsettling weather activity persisted throughout the southeastern quadrant
of the nation on Monday. Numerous showers, thunderstorms, locally heavy
rainfall, and strong to damaging winds developed from southeastern Texas to the
Mid-Atlantic Coast as a trough of low pressure dipped across the Tennessee
Valley and the Appalachians and a frontal boundary remained draped across the
Central Gulf Coast. Abundant moisture from the Gulf of Mexico and daytime
heating heightened instability and weather activity intensity in the Southeast
during the afternoon. Heavy concentrations of precipitation created risks of
flash flooding, while strong thunderstorms created a chance for occasional cloud
to ground lightning strikes. Meanwhile, another cold and gloomy day developed in
the northern tier of the nation. Widespread clouds engulfed much of the Northern
and Central Plains through the Northeast, while a cold high pressure system
became stretched from the Upper Midwest through the Northeast. Areas of snow
fell in the Upper Mississippi Valley, while daytime temperatures of the
aforementioned regions remained at below seasonal averages. Dense cloud coverage
also blanketed the Central and Southern Plains as a frontal boundary reached
into the Central Plains on Monday. Moist air lifted over this frontal boundary
produced areas of dense fog and drizzle in western Texas. In the West, energy
and moisture from an approaching Pacific storm began to filter into the Pacific
Northwest and California. Cloudy skies covered much of the coastal states, while
increasing winds affected northern California through the afternoon. The threat
of significant precipitation and possible isolated thunderstorms remained over
the region.
Relatively inactive weather tracked
through the country on Friday ahead of an active weekend in parts of the
country. A long front draped across the Southeast and produced areas of showers
and thunderstorms that slowly moved off the Gulf Coast and into the peninsula of
Florida. Also, moist flow into the Northeast instigated areas of scattered
showers in New England. A few early season snow showers also develop in the area
but quickly diminished in the late afternoon. A few rain and snow showers were
also noted in the Northern Plains but also waned into the afternoon. A Pacific
storm also renewed some showers in the Northwest, but most of this precipitation
fell in western Washington. After heavy rain early in the week, dry and hot
conditions were dominant in the Southwest and California. The middle portion of
the country was also dry. The Northeast rose into the 40s, while the Southeast
saw a range of temperatures from the 50s to the 80s. The Northern Plains rose
into the 30s and 40s, while the Southwest saw temperatures in the 80s, 90s, and
some 100s.
18th-24th…Widespread
clouds engulfed New Mexico and Colorado as an energetic low pressure system
moved through northern New Mexico into the Texas Panhandle and western Oklahoma
on Wednesday. Areas of light rain and snow showers continued to fall across New
Mexico through the afternoon. Strong flow associated with this system spread
into Colorado and produced a swath of light to moderate mixed precipitation in
eastern Colorado. Heavy snowfall blanketed the Sangre De Cristo Mountains and
the southern I-25 corridor from south of Colorado City to the the New Mexico
Border. Gusty, northeast wind accompanied heavy snowfall, creating blowing and
drifting snow with lowered visibilities. As the aforementioned system trekked
toward southwestern Kansas, light to moderate, widespread showers and isolated
thunderstorms developed in northern Texas, western and central Oklahoma, and
Kansas. Persistent rainfall threatened these areas with localized flooding
through the afternoon. Meanwhile, an associated front hammered the Central
Plains, Upper Mississippi Valley, and the Upper Great Lakes with mixed
precipitation and a few embedded thunderstorms as it became stretched from
Kansas through northern Michigan. A wave of low pressure along the front kicked
up heavy snowfall in northeastern Minnesota and significant rainfall in northern
Wisconsin. Elsewhere, a cold front from the Eastern Pacific brought light
showers and mostly cloudy skies to the Pacific Northwest as it moved across the
Northwest Coast. California and the western halves of the Central Great Basin
and the Southwest remained under seasonal weather conditions due to a flat ridge
of high pressure located over the West Coast. High pressure located off the
Mid-Atlantic Coast produced fair weather throughout much of the East, with
warmer temperatures near the Mid-Atlantic shoreline.
25th-31st…A
cold front continued tracking eastward through the country on Monday and allowed
for heavy rains over the South. A low pressure system that developed over the
Rockies and moved into the Great Lakes, while flow around this system created a
frontal boundary that extended down the Mississippi Valley and into the Southern
Plains. This forced ample moisture to pour in from the Gulf of Mexico, and
allowed for showers and thunderstorms to develop over eastern Texas and Oklahoma
as well as the Lower Mississippi Valley. In Lufkin, Texas, 2.02 inches of rain
was reported and highs over the region only reached into the upper 50s and lower
60s. Some of these storms turned severe with strong wind gusts up to 81 mph
reported in Christi, Texas. Lighter showers stretched toward the Great Lakes,
with less than a tenth of an inch reported in most areas. However, heavy rains
in the South have allowed for severe flooding problems over the Lower
Mississippi region. Just to the east, a front pushed in from the Atlantic Ocean
and kicked up light and scattered showers over the Mid-Atlantic states. Rainfall
totals remained less than a tenth of an inch, but the region saw humid
conditions with highs near 60. Moving up the East Coast, high pressure lingered
over the Northeast and brought mostly sunny skies with cool conditions.
Overnight lows dipped to freezing, while daytime highs hovered in the 40s. To
the West, a trough of low pressure pushed over the Pacific Northwest and brought
scattered showers with snow at higher elevations. A half of an inch of rain was
reported at Locks, Oregon as up to 3 inches of snow fell over the Cascades and
Northern Rockies. The rest of the West Coast remained sunny and warm on Monday.
A
blustery day of winter weather developed in the West on Wednesday as a strong
and cold trough of low pressure dug across the Four Corners. Cold air from the
north plunged into the region and dampened daytime temperatures throughout the
West. A considerable amount of moisture wrapped around the system to produce
moderate to heavy snowfall across the higher elevations of the region,
especially the Laramie Mountains in Wyoming, the Utah Mountain ranges, and the
Central Rockies. Gusty winds accompanied wintry precipitation, increasing
hazardous traveling conditions. Meanwhile, the frontal system associated with
this trough moved into the Northern and Central Plains during the afternoon.
Light snowfall and strong winds began to affect Nebraska, while a few light
showers developed across the western Oklahoma Panhandle and the northwestern
Texas Panhandle. In the East, a low pressure system trekked through the Ohio
Valley and the Mid-Atlantic region produced fairly gloomy weather conditions
from the Upper Great Lakes through the Northeast. Moderate to locally heavy
rainfall developed throughout areas of New England.
The
most notable storm that tracked through the country was a low pressure system
that spilled out of the Rockies and into the Plains. This storm brought early
season snowfall to the Central Rockies where many locations received over a foot
of snow and some locations received nearly three feet of snow. This is a
significant amount of snow for so early in the season. Various Winter Storm
Warnings were in effect from northern New Mexico through North Dakota in
anticipation of more snow. This storm was one of those interesting Fall storms
that produced significant snow in the Rockies, while also also instigating
widespread rain and thunderstorms in the Plains and Mississippi Valley. Tornado
Watches were in effect in the Lower Mississippi Valley due to the possibility
that some of the thunderstorms could turn severe. Rain also spread into the
Upper Midwest and Upper Mississippi Valley as the day progressed. Cold air
continued to spill into the Intermountain West and Rockies and actually
plummeted as far south as New Mexico. Elsewhere, morning showers in the
Northwest diminished as the day progressed, while a high pressure system kept
conditions dry in the Northeast and along the rest of the eastern seaboard. The
Northeast rose into the 40s and 50s, while the Southeast saw temperatures in the
70s, 80s, and some 90s. The Rockies rose into the 20s and 30s, while the
Northwest saw temperatures in the 40s and 50s.
The
storm that dropped a tremendous amount of early season snow on the Rockies on
Wednesday and Thursday moved through the Plains on Friday. As it moved into the
Upper Midwest, its associated cold front swept through the Mississippi Valley
and instigated another round of tremendous precipitation. Moderate to heavy rain
fell along the front from the Gulf Coast through the Upper Mississippi Valley.
Some thunderstorms along the southern edge of the front were strong enough to
allow Tornado Watches to be posted in parts of the Southeast. Flood Watches and
Warnings were also posted from eastern Texas through the Upper Mississippi
Valley due to the tremendous amount of rain that fell on the area. Snow showers
did eventually stop in the Rockies, but cool air in the Rockies and Northern
Plains dampened daytime high temperatures in the area. The storm also produced
strong winds from the Northern Plains through the Appalachians.
High
pressure along the eastern seaboard produced dry conditions for another day. The
West also remained dry under a high pressure system. The Northeast rose into the
40s, 50s, and 60s, while the Southeast saw temperatures in the 70s, 80s, and
some 90s. The Northern Plains rose into the 30s and 40s, while the Southwest saw
temperatures in the 60s and 70s.
Jim G. Munley, jr.
http://www.goecities.com/jimmunleywx
