A joint service of the UK Ag Weather Center and the National Weather Service.
A dry cold front is pushing southward through the forecast area
today, noted by the wind shift to the northwest across the
northwestern tier of counties. The front will continue to push
southward overnight, with light northerly winds areawide by
sunrise. Airmass remains relatively dry and do not expect anything
more than a cirrus deck streaming across the area. Overnight lows
will be in the upper 20s far northwest to upper 30s southeast.
Friday through Wednesday.
Strong west-southwest flow aloft will be in place over much of
the eastern CONUS on Friday between troughing centered over
eastern Canada and the northeastern CONUS and subtropical ridging
centered near the Greater Antilles. A shortwave will be moving
through the northeastern CONUS trough with a shearing axis of
vorticity extending southwestward to a cutoff low centered over
the Gulf of California and northwest Mexico. This shortwave and
a surface high moving into the Southern Plains will push the cold
front south of the area. Northwesterly low-level flow behind the
front will maintain a dry air mass below 600mb and prevent any
measurable precipitation despite strong upper-level forcing for
ascent. Expect just an increase in mid and high level clouds, with
some virga across the far southern counties. Couldn't rule out a
stray sprinkle there, but chances are too low to mention in the
forecast at this time. Low-level cold air advection will bring in
925mb temperatures around 0C across the north. This will result in
a cool day with highs only in the low to mid 40s across the north,
with upper 40s to low 50s south. Skies should clear out Friday
night with the exception of some cirrus from the subtropical jet.
With calm winds expected as surface high pressure slides eastward
across the Deep South, and a dry air mass, expect strong
radiational cooling with lows in the upper 20s to around 30, and
some low to mid 20s in the typically colder locations.
A trough digging into the western CONUS will serve as a kicker to
cause the cutoff low over Mexico to eject across Texas as a
negatively tilted trough Saturday and Saturday night. Ridging will
build in aloft across the Deep South ahead of this feature. Flow
above the surface will become southwesterly, but an easterly
component to winds at the surface due to high pressure moving into
Georgia will keep high temperatures in check, remaining in the
50s. Dry air will remain in place at low-levels, with only mid and
high level clouds expected during the day and evening. A 40-50 kt
LLJ will strengthen over the Lower Mississippi Valley after
midnight Saturday night. A weak surface low that develops along
the old frontal boundary in the northwest Gulf due to forcing
associated with the trough will also lift northward across this
area. Models have trended slower with the onset of precipitation
in West Alabama late Saturday night, and it may hold off until
Sunday morning. However, will keep in a chance of scattered
showers in the west for now given strong warm air
advection/isentropic lift if the dry air at the surface can be
overcome. Lows will be in the upper 30s to low 40s, with low to
mid 30s possible in the northeast. Many areas will probably see
their low temperatures in the evening before rising after
midnight. Strong warm air advection will prevent any wintry
The shortwave trough will be in the process of shearing/weakening
as it lifts northward towards the Ohio Valley, while deep layer
moisture will continue to increase. There are some model
discrepancies in QPF that begin to appear due to the decrease in
upper-level forcing behind the shortwave and the potential for
convection along the Gulf Coast. Will focus the highest PoPs
generally west of I-65 where the best LLJ will be. At the surface,
a warm front will try to lift northward into our southern
counties, but its northward progression will be restricted
initially by evaporative cooling as rain falls into the lingering
dry air mass across the area. This will limit high temperatures
and instability during the day on Sunday, and have removed the
slight chance of thunder from the southern counties during this
Moist deep layer southwesterly flow remains in place on Sunday
night ahead of a trough over the western CONUS. The ECMWF has
trended towards the GFS with a wetter solution during this time.
PWATs will increase to 1.5 to 1.8 inches, which is at or above the
95th percentile for December. Dewpoints will climb into the 60s
across the southern counties which could allow for some weak
instability and thunderstorms to be possible. But the LLJ will
have weakened by this time with little upper-level forcing and
weak lapse rates, so severe storms are not expected at this time.
Monday through Wednesday:
Forecast confidence becomes low by this time period. The GFS
continues to indicate a wetter solution, keeping a more phased
trough to the west of the area. Meanwhile the ECMWF pushes the
northern portion of this trough quickly eastward while indicating
a cutoff low in the southern stream over northwest Mexico. Overall
it seems the ECMWF has trended slightly more to the GFS, and the
EPS ensemble mean/a fair number of EPS members are wetter than the
deterministic ECMWF. Therefore have tended towards a wetter
solution for Monday and Tuesday, but kept PoPs in the chance
range. The GFS keeps high PWATs around during this time, with
unidirectional flow indicating the potential for training and the
possibility of a couple rounds of heavier rainfall. Flash flood
guidance is high across the area given recent dry conditions, so
the ground could handle 1 or 2 rounds of rain but localized
flooding could develop if multiple rounds develop. Will hold off
on mention any flooding threat in the HWO at this time given
inherent uncertainty with QPF and the model differences.
The GFS dries out the area by Wednesday, while the ECMWF brings
some precipitation across the Gulf Coast associated with the
remnants of the cutoff low. Will keep a dry forecast going during
Alabama Forecast Discussion (NWS)
National Ag. Weather Outlook, International Ag. Weather Summary
Current Surface Map,
[2nd Source TWC]
Click here for UKAWC Point Agricultural, Lawn & Garden Forecast/Outlook in case of corrupt tables.
Regional Hourly Observations For COLBERT County
300 AM CST FRI DEC 15 2017
CITY SKY/WX TMP DP RH WIND PRES REMARKS
SHOALS AIRPORT CLOUDY 28 23 81 CALM 30.10F
SHOALS TVA RES N/A 27 N/A N/A MISG N/A
Current Agricultural Weather Conditions in Alabama
Based on observations at 300am CST, Friday December 15, 2017
Across Alabama...temperatures are near 27 degrees north, near 33 degrees central, and near 48 degrees south. Current sky conditions are partly cloudy north, partly cloudy central, and cloudy south. In the north, relative humidity is near 92%, and the dew point is near 25 degrees. In the central part of the state, relative humidity is near 75%, and the dew point is near 26 degrees. In the south, relative humidity is near 86%, and the dew point is near 44 degrees. Winds are calm north, where conditions are favorable for spraying. Winds are from the north at 7 mph central, where conditions are favorable for spraying. The wind chill is near 27 degrees central. Winds are from the west at 3 mph south, where conditions are favorable for spraying. The livestock cold stress index is in the no stress category north, no stress category central, and no stress category south. Based on current available observations, the highest temperature is 50 degrees at Brookely Field. The lowest temperature is 27 degrees at Decatur.
Current NOWCAST not available:
Nowcasts are not issued routinely during fair weather. Only when
precipitation or other significant weather is occuring in this county will these
forecasts be issued. Currently, there is no short term forecast in effect.
U.S. Radar Map,
All NWS Radars (In near-real time),
Current Livestock Heat Stress Index (LSI),
Current Wind Chill Map
Hazardous Weather Outlook For COLBERT County, AL
256 AM CST Fri Dec 15 2017
DAY ONE Today and Tonight
No hazardous weather is expected at this time.
DAYS TWO THROUGH SEVEN Saturday through Thursday
The probability for widespread hazardous weather is low.
Isolated ordinary thunderstorms will be possible on Monday and
Monday night as a cold front passes over the region.
SPOTTER CALL TO ACTION STATEMENT
Activation of storm spotters and emergency management personnel is
not anticipated at this time.
NWS Severe Weather Map , Convective Outlook
7-Day Forecast For COLBERT County, Alabama
227 AM CST Fri Dec 15 2017
EARLY THIS MORNING
Mostly cloudy. Northwest winds around 5 mph.
TODAY Mostly cloudy in the morning, then becoming partly cloudy.
Highs in the mid 40s. Northwest winds 5 to 10 mph.
TONIGHT Clear. Lows in the upper 20s. Southwest winds around
SATURDAY Sunny. Highs in the mid 50s. South winds 5 to 10 mph.
SATURDAY NIGHT Mostly cloudy. A slight chance of showers after
midnight. Lows in the upper 30s. South winds around 5 mph. Chance of
rain 20 percent.
SUNDAY Showers. Highs in the mid 50s. Southeast winds 5 to
10 mph. Chance of rain 90 percent.
SUNDAY NIGHT AND MONDAY Mostly cloudy with a 40 percent chance of
showers. Lows in the upper 40s. Highs in the upper 50s.
MONDAY NIGHT Mostly cloudy with a chance of showers with a slight
chance of thunderstorms. Lows in the upper 40s. Chance of rain
TUESDAY Mostly cloudy with a 40 percent chance of showers. Highs
in the lower 60s.
TUESDAY NIGHT Partly cloudy in the evening, then clearing. Lows
in the upper 30s.
WEDNESDAY AND WEDNESDAY NIGHT Mostly clear. Highs in the upper
50s. Lows in the upper 30s.
THURSDAY Sunny in the morning, then becoming partly cloudy. A
20 percent chance of showers. Highs around 60.
12-48 Hr Surface Forecast Maps,
TWC 4-Panel Surface Forecast,
Day 1 Precip,
Day 2 Precip,
Days 1-5 Precip,
Severe Weather Pot.-Day 1,
Medium & Long Range Outlook For Alabama
6 TO 10 DAY 8 TO 14 DAY 30 DAY 90 DAY
DEC 20-24 DEC 22-28 DEC DEC-FEB
----------- ----------- -------- ---------
Temperature: Above Above Above Above
Precipitation: Above Above Below Below
.... Medium and long range outlooks provided by NCEP/K. Thomas Priddy
5 Day Rainfall Forecast,
6 to 10 Day ,
8 to 14 Day ,
Friday December 15, 2017 the 349th Day of Year
Distance 0.999725 AU
Rise 07:45 EST Set 17:42 EST
Transit Meridian 12:43 EST
Civil Twilight Begins 07:19 EST Ends 18:08 EST
Calculations made for central point in the state.
Time in ET -- and will vary due to location and
elevation -- Priddy
Historical Weather And Climate Facts For Today
HISTORIC WEATHER EVENTS
The first of triple storms hit Massachusetts Bay. The storm produced whole
gales, and more than 20 inches of snow in interior New England. There was
great loss of life at Gloucester MA. (David Ludlum)
An intense cold front swept across the eastern U.S. The cold front produced
heavy rain in Louisiana, and heavy snow in the northeastern U.S. (David
A record December snowstorm buried Buffalo NY under 36.6 inches of snow,
with unofficial totals south of the city ranging up to 70 inches. Travel
was brought to a halt by the storm. (14th-17th) (The Weather Channel)
A major winter storm hit the Great Lakes Region, intensifying explosively
as it crossed northern Illinois. High winds and heavy snow created blizzard
conditions in southeastern Wisconsin. Winds gusted to 73 mph, and snowfall
totals ranged up to 17 inches at LaFarge. The barometric pressure at
Chicago IL dropped three quarters of an inch in six hours to 28.96 inches,
a record low reading for December. Up to a foot of snow blanketed northern
Illinois, and winds in the Chicago area gusted to 75 mph. O'Hare Airport in
Chicago was closed for several hours, for only the fourth time in twenty
years. High winds derailed train cars at Avon IN. Light winds and partly
sunny skies were reported near the center of the storm, a feature typical
of tropical storms. (The National Weather Summary) (Storm Data)
High pressure in the Pacific Northwest and low pressure in the southwestern
U.S. combined to produced high winds from Utah to California. Winds gusting
to 70 mph in the San Francisco area left nearly 300,000 residents without
electricity. Winds in Utah gusted to 105 mph at Centerville. (The National
Weather Summary) (Storm Data)
A couple of low pressure systems spread heavy snow across the northeastern
U.S. Up to two feet of snow was reported along Lake Erie in northeastern
Ohio, and up to ten inches was reported in Connecticut. Heavy snow squalls
developed over Michigan for the third day in a row. Three Oaks MI reported
25 inches of snow in two days. Twenty-six cities in the north central U.S.
reported record low temperatures for the date. The low of 10 degrees below
zero at Wichita KS was a December record for that location. (The National
Weather Summary) (Storm Data)
Ag Weather Center, Department of Biosystems & Agricultural Engineering, University of Kentucky