Drought in Florida, January 1 to 31, 2012

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TALLAHASSEE FL
739 PM EST Sat Dec 31 2011

.SYNOPSIS...The weather across the Southeast was generally
tranquil early this evening with a low-level high pressure ridge
maintaining control on the regional weather for another night. At
dusk, temperatures ranged from the mid-60s near the Gulf coast to
the mid-50s across much of the mid-South and southern Appalachian
Mountains with light west to southwest winds.

Meanwhile, a strong cold front surging into the Plains in the
central part of the country signals upcoming changes to the
weather along the east coast in the first part of the new year. A
powerful and potent shortwave trough was digging into the central
Plains from Wyoming and Colorado. The developing extratropical
cyclone and associated surface low will deepen and push northeast
into the Great Lakes on Sunday, and Quebec by Monday, which will
drive the cold front through our forecast area about 24 hours from
now. The amplifying flow pattern and deep cyclone in southeast
Canada will set up a north-northwest flow from the Canadian
Arctic into the eastern half of the United States. This will
enable a secondary cold front to push into the region on Monday,
with a shallow cold air mass pushing in behind the front. This
arctic air mass will be modifying as it pushes south, but should
still be chilly enough to provide several cold nights on Monday
Night and Tuesday Night. More details are discussed in the
previously issued AFD...appended below the updated sections.

&&

.UPDATE...The main concern with this evening's updates surround
dense fog potential during the overnight period. With the majority
of both high-resolution and statistical model guidance on board
with widespread fog and low visibilities, a Dense Fog Advisory was
issued for the majority of the land areas (except far northeastern
counties in Georgia), and for the marine zones within 20NM of the
coastline. This fog is likely to develop initially near the coast,
perhaps partially over water as well as in low-lying areas near
the Gulf, before expanding north overnight. Our local 4km WRF-ARW
and other high-resolution model guidance suggests that dense fog
could become a concern as early as 02-03z in our Florida zones,
but should hold off until after Midnight further north.

The set up seems pretty classic for widespread fog. In addition to
clear skies and light winds, the 00z KTAE sounding showed a strong
deep subsidence inversion with a base around 875mb (4000 ft). Low-
level moisture is projected to increase underneath this inversion
tonight, with 0-1km mixing ratios rising by 1-2 g/kg. The added
moisture combined with efficient radiational cooling are a recipe
for widespread fog again tonight. The VSREF has probabilities of
1/4SM visibility 70-90% across basically the entire area.

As we saw with visible satellite this past morning, river valleys
and lakes could be a favored location for dense fog. With
dewpoints in the mid-40s still in our far NE Georgia forecast
zones, and elevation about 100-200 ft higher than surrounding
areas, we opted not to bring the advisory that far north yet. This
will be monitored through the evening in case it needs to be
expanded further north into areas like Tifton and Fitzgerald.
Finally, with New Years weekend holiday travel, dense fog tonight
could have a greater impact to motorists.

All the evening updated products are out early to account for the
new Dense Fog headline.

&&

.AVIATION...Dense fog is the main concern tonight with guidance
and persistence strongly in favor. The fog is expected to start
first across the Florida terminals and then gradually develop
northward across the Alabama and Georgia terminals later in the
night. A relatively early onset is expected across Florida with
the KTLH vis starting to drop around 03z and dense fog possible
before midnight. Fog is expected to last into the mid-morning
hours with dissipation occurring sometime between 14-16z. VFR is
expected for the rest of the day.

&&

.PREV DISCUSSION (issued at 355 PM EST Sat Dec 31)...

SHORT TERM (Sunday through Monday Night)...Sunday, overall upper
level pattern will further amplify as the trough over the mid-
section of the county moves east and begins to phase with
additional shortwave energy from the north. A weak cold front
ahead of this feature will move into our western zones by early
afternoon and then pass east of our area Sunday evening. Expecting
Sunday to start out with areas/widespread fog across the eastern
zones. Due to the weak sun angle, the fog will likely linger
through much of the morning. Forecast is a bit trickier further
west toward Panama City and Dothan in closer proximity to the
approaching front. Will clear the dense fog out of these western
zones a few hours earlier as a gradient tightens and promotes more
efficient mixing during the morning hours. Will keep PoPs around
10% with this frontal passage as the overall column moisture and
synoptic forcing is not impressive. Will add sct sprinkles to the
grids as most guidance members are showing some light QPF. Doubt
most areas will see measurable precip, but a few raindrops can not
be ruled out.

Sunday night, a drier and noticeably cooler airmass (although not
unusual) will filter in during the night behind Sunday's front.
Skies will be clearing with a steady NW breeze. Still not
expecting any freezing temperatures as low temps will range from
the middle 30s north of Dothan and Albany to the lower 40s south
and east of Tallahassee and Valdosta.

Monday/Monday night, a significant amplification to the upper
level pattern will occur during the daylight hours with an
impressive trough across the eastern third of the nation by the
end of the day. This amplification will be accompanied by a strong
surge of arctic air into the eastern states. This stronger more
arctic configuration front is not scheduled to arrive until Monday
evening. Therefore, much of our area will reside within the
thermal ridge ahead of the front Monday afternoon, with
temperatures climbing into the middle and upper 50s. The big
change will occur Monday evening as the arctic front quickly
passes through. As of the 12Z guidance cycle, the ECMWF/Canadian
and UKMET all show 850mb temps down between -8 and -10C around
KTLH and -12C up toward Albany and Tifton by sunrise. The GFS
remains an outlier on the warm side, with 850mb temps over the CWA
up to 10C warmer than the other global guidance members. Going to
side with the colder guidance consensus, which is also in
agreement with HPC. The resulting forecast will show a widespread
advection freeze Monday night. A steady northwest wind will add to
the cold with windchill values down into the upper teens by
sunrise.

LONG TERM (Tuesday morning through next Saturday)...The main surge
of arctic air will advect into our forecast area by early Tuesday.
While all of the numerical guidance shows a deep long wave 500 mb
trough over the eastern U.S. and a strong arctic surface high
diving southward into the Southern Plains, the solutions differ as
to just how cold it will be here. The NAM, ECMWF, and CMC are very
cold with an 850 mb temperature around -9 deg C at Tallahassee
early Tuesday. The outlier GFS is a good 10 deg C warmer than
this. The GFS may be correct, but it seems prudent at this point
to average the colder solutions into our forecast so that we don't
miss too badly if the GFS is too warm. Despite the winds remaining
in the 5-10 MPH range most of Monday night, lows will likely fall
well below freezing over our entire forecast area (even at the
beaches). We may meet our local wind chill advisory criteria for
the first time this season. Even if the warmer GFS verifies, GFS
BUFKIT soundings indicate highs will struggle to reach the mid
40s, which is several degrees colder than the GFS MOS. All the
global NWP guidance continues to forecast the arctic surface high
to become centered over Tallahassee Wednesday morning. This will
allow the winds to become calm overnight. With calm winds,
dewpoints around 10 degrees, and one of the longest nights of the
year, we think low temperatures will plummet more than what the
GFS MOS is currently forecasting (mid 20s). Near-record lows in
the upper teens seem more likely given such a favorable cooling
setup, with mid to upper 20s at the coast and in the larger
cities.

We looked back at two of the coldest recent arctic outbreaks here
(that occurred without snow) and found some similarities to this
forecast. The two that we examined where the January 1985 and
December 1983 outbreaks, both of which set records locally. Early
indications are that this upcoming outbreak will not be quite as bad
given that the surface high may be slightly weaker, and the 850 mb
cold pool is not expected to be quite as expansive as was observed
in the previous cases. However, we will continue to monitor
subsequent model trends as these short-lived arctic outbreaks can
produce surprisingly cold temperatures in the Deep South, even when
the winds are not calm.

A slow warming trend will begin Wednesday afternoon, though the GFS
MOS appears to be bouncing back toward climatology too quickly, and
we plan to slow this warming down a bit. In fact, the surface high
will still be in a favorable position for another freeze Thursday
morning, but a weak upper level trough passing by may bring enough
upper level moisture to counteract the boundary layer cooling.

The 00 UTC GFS and ECMWF forecast a weak cold front west-northwest
of our forecast area by Saturday. The GFS solution is more
progressive while the ECMWF appears to stall the front too far away
for any rain for our area. Given how far out this and the recent
inconsistencies in the GFS for this time frame, we will leave out
any mention of PoP above 10 percent. Milder temperatures will return
Friday and Saturday.

MARINE...A surface ridge of high pressure over the northeast Gulf
of Mexico will keep winds and seas low through tonight. A cold
front will then cross the forecast waters Sunday and Sunday
evening. Winds will shift northerly in the wake of this front and
quickly increase to advisory levels. A secondary cold front will
then cross the forecast waters Monday evening helping to keep
winds and seas elevated to advisory levels. The current forecast
will reflect a pattern more in line with the ECMWF/Canadian/UKMET
consensus solutions. These guidance members bring a stronger push
of cold air advection compared to the outlier GFS solution.
Therefore, wind gusts are forecast to approach gale force at times
Monday night, especially over the offshore legs. Winds and seas
will then quickly decrease Tuesday night into Wednesday as another
ridge of high pressure builds over the region.

FIRE WEATHER...Red Flag conditions are unlikely through Sunday.
However, very dry air will increase the threat for Red Flag
conditions on Monday and Tuesday as cold, very dry air moves into
the region on gusty northwest winds.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   49  75  40  57  25 /   0  10  10   0   0
Panama City   58  74  42  56  29 /   0  10   0   0   0
Dothan        52  72  37  54  25 /  10  10   0   0   0
Albany        48  72  36  53  25 /   0  10   0   0   0
Valdosta      48  74  39  54  25 /   0  10  10   0   0
Cross City    47  74  43  58  26 /   0   0  10   0   0
Apalachicola  56  71  41  57  29 /   0  10  10   0   0

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...Dense Fog Advisory from Midnight tonight to 9 AM CST Sunday for
     Coffee-Dale-Geneva-Henry-Houston.

GA...Dense Fog Advisory from 1 AM to 10 AM EST Sunday for Baker-
     Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-Decatur-Dougherty-
     Early-Grady-Lanier-Lowndes-Miller-Mitchell-Quitman-Randolph-
     Seminole-Thomas.

FL...Dense Fog Advisory until 10 AM EST /9 AM CST/ Sunday for all
     forecast zones in Florida.

GM...Dense Fog Advisory until 10 AM EST Sunday for all of the
     coastal waters zones within 20 NM of shore.

&&

Synopsis/Update...Lamers
Aviation...Van Dyke
Short Term...Mroczka
Long Term...Fournier
Marine...Mroczka
Fire Weather...Lanier

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TALLAHASSEE FL
512 PM EST SAT DEC 31 2011

ALZ065>069-FLZ007>019-026>029-034-108-112-114-115-118-127-128-134-
GAZ120>131-142>148-155>161-011100-
COFFEE-DALE-HENRY-GENEVA-HOUSTON-INLAND WALTON-CENTRAL WALTON-
HOLMES-WASHINGTON-JACKSON-INLAND BAY-CALHOUN-INLAND GULF-
INLAND FRANKLIN-GADSDEN-LEON-INLAND JEFFERSON-MADISON-LIBERTY-
INLAND WAKULLA-INLAND TAYLOR-LAFAYETTE-INLAND DIXIE-SOUTH WALTON-
COASTAL BAY-COASTAL GULF-COASTAL FRANKLIN-COASTAL JEFFERSON-
COASTAL WAKULLA-COASTAL TAYLOR-COASTAL DIXIE-QUITMAN-CLAY-
RANDOLPH-TERRELL-DOUGHERTY-LEE-WORTH-TURNER-TIFT-BEN HILL-IRWIN-
EARLY-MILLER-BAKER-MITCHELL-COLQUITT-COOK-BERRIEN-SEMINOLE-
DECATUR-GRADY-THOMAS-BROOKS-LOWNDES-LANIER-
512 PM EST SAT DEC 31 2011 /412 PM CST SAT DEC 31 2011/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST ALABAMA...
SOUTHWEST AND SOUTH CENTRAL GEORGIA...AND THE FLORIDA BIG BEND
AND PANHANDLE.

...SIGNIFICANT FREEZE POTENTIAL FOR MONDAY AND TUESDAY NIGHTS...

.DAY ONE...TONIGHT...

DENSE FOG IS EXPECTED TO DEVELOP QUICKLY THIS EVENING IN PARTS OF
THE FLORIDA PANHANDLE AND BIG BEND...AND THEN EXPAND NORTH INTO
ADJACENT SECTIONS OF SOUTHEAST ALABAMA AND SOUTHWEST GEORGIA
OVERNIGHT. CURRENT INDICATIONS ARE THAT THE DENSE FOG COULD BE
QUITE WIDESPREAD. ANY FOG THAT DOES DEVELOP MAY HAVE A GREATER
IMPACT TO MOTORISTS WITH NEW YEARS HOLIDAY TRAVEL THIS WEEKEND.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY...

A COLD FRONT WILL PASS THROUGH THE AREA ON SUNDAY BRINGING WITH IT
A SIGNIFICANT FREEZE POTENTIAL FOR MONDAY AND TUESDAY NIGHTS. THE
COOLER AIR WILL BEGIN TO FILTER INTO THE AREA ON MONDAY WITH
NORTHWEST WINDS...AND THE TEMPERATURES WILL CONTINUE TO PLUMMET
THROUGH MONDAY NIGHT. THE AIR TEMPERATURES WILL BE FALLING INTO
THE MIDDLE 20S LATE...AND WINDS BETWEEN 5 AND 10 MPH WILL PRODUCE
WIND CHILLS IN THE UPPER TEENS AFTER MIDNIGHT. ON TUESDAY
NIGHT...RECORD LOW TEMPERATURES WILL BE POSSIBLE AS TEMPERATURES
ARE FORECAST TO FALL INTO THE UPPER TEENS AND LOWER 20S. SLOWLY
MODERATING TEMPERATURES ARE FORECAST FOR THE REST OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE
WEBSITE ON THE INTERNET AT WEATHER.GOV...THEN CLICK ON YOUR AREA
OF INTEREST ON THE NATIONAL MAP.

GMZ730-750-755-765-770-775-011100-
APALACHEE BAY OR COASTAL WATERS FROM KEATON BEACH TO OCHLOCKONEE
RIVER FL OUT TO 20 NM-
COASTAL WATERS FROM APALACHICOLA TO DESTIN FL OUT 20 NM-
COASTAL WATERS FROM  OCHLOCKONEE RIVER TO APALACHICOLA FL OUT TO
20 NM-
COASTAL WATERS FROM  SUWANNEE RIVER TO KEATON BEACH OUT 20 NM-
WATERS FROM APALACHICOLA TO DESTIN FL FROM 20 TO 60 NM-
WATERS FROM  SUWANNEE RIVER TO APALACHICOLA FL FROM 20 TO 60 NM-
512 PM EST SAT DEC 31 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ADJACENT COASTAL WATERS
OF THE FLORIDA BIG BEND AND PANHANDLE.

.DAY ONE...TONIGHT...

SOME FOG MAY DEVELOP TONIGHT...MAINLY IN WATERS WITHIN A FEW MILES
OF THE SHORELINE AND OVER APALACHEE BAY. WATER TEMPERATURES IN
THESE AREAS ARE COOLER...CLOSER TO 60 DEGREES...AND AS LOW LEVEL
MOISTURE INCREASES OVERNIGHT THOSE AREAS WILL BE MORE PRONE TO FOG
DEVELOPMENT. VISIBILITIES BELOW ONE MILE WILL BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY...

A COLD FRONT WILL PASS THROUGH THE AREA LATE SUNDAY. AS COLD AIR
POURS INTO THE AREA BEHIND THE FRONT ON MONDAY AND TUESDAY...
STRONG WINDS ARE LIKELY TO DEVELOP OVER THE COASTAL WATERS.
SUSTAINED WINDS OF BETWEEN 20 AND 30 KNOTS ARE EXPECTED...WITH
GUSTS OF GALE FORCE POSSIBLE. SEAS MAY BUILD TO 8 TO 9 FEET IN
OFFSHORE AREAS LATER ON MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE
WEBSITE ON THE INTERNET AT WEATHER.GOV...THEN CLICK ON YOUR AREA
OF INTEREST ON THE NATIONAL MAP.

08-LAMERS