Area Forecast Discussion
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FXUS62 KTAE 131714

Area Forecast Discussion
National Weather Service Tallahassee FL
1214 PM EST Wed Dec 13 2017

.AVIATION [Through 18Z Thursday]...

VFR conditions and relatively light winds will prevail through the
TAF. High cloudiness is expected to spread eastward over ECP and
TLH later this evening.



.NEAR TERM [Through Today]...

The axis of the east coast trough will continue to push into the north
atlantic while a weak shortwave trough moves across the MO valley
this afternoon. In our area, mid level flow will be established
downstream of cutoff low over Baja California and overtop building
surface ridge across the Gulf of Mexico. Clear skies will continue
for today with wind directions eventually shifting to the southwest
as the surface high center moves over the FL peninsula. This will
cause moisture to increase mainly beginning late this afternoon.
Highs will top out in the mid to upper 50s.

.SHORT TERM [Tonight Through Friday]...

Clear and quiet conditions will give way to increasing clouds and a
low end chance for weak showers Thursday and Friday, as a
reinforcing shortwave trough dives out of the Northern Rockies/Great
Plain/Lower Mississippi Valley into the southeast by late
Thursday. This feature will tap into sub-tropical moisture
currently streaming into southern Baja California and western
Mexico around a cut off mid-level low centered over the Gulf of
California. This moisture will stream into the area late Thursday
into Friday, yielding an increase in mid and upper level clouds.
An associated surface front is expected to slide into the region
and is expected to stall along the Gulf Coast/northern Gulf of
Mexico late Thursday into Friday, providing a focal point for
shower development Thursday night and Friday, before drier air
filters into the region late Friday night. At this time, POPs
generally range from 30 to 50% for Thursday night/Friday morning,
with the highest POPs currently offshore. The placement of the
aforementioned surface front will likely influence exactly where
the highest rainfall chances will be located. However, the bottom
line is that coastal locales will have the best chances for
showers during this timeframe. Afternoon highs will run a few
degrees above average on Thursday (upper 60s to near 70),
returning to near average on Friday (low to mid 60s) with increase
cloud cover and the frontal passage. Overnight lows will remain
near average, in the low to mid 40s.

.LONG TERM [Friday Night Through Wednesday]...

Drier conditions will be limited to Saturday, as a brief shortwave
ridge traverses the region ahead of a series of approaching
shortwave troughs. The aforementioned cut off mid-level low over the
Gulf of California will get ejected eastward by a kicker trough,
diving southeastward out of the Gulf of Alaska, breaking down the
stagnant ridge off of the west coast. This pattern change will open
the door for an active long term period, as medium range guidance
currently shows several potent shortwave troughs traversing the
region through mid next week. Abundant sub-tropical moisture will be
in place across the region through this period, allowing for
appreciable shower and perhaps thunderstorm chances Sunday through
the early part of the week. While the latest guidance is in good
agreement regarding an overall pattern change, it is important to
note that there are some differences regarding how progressive and
moist the second shortwave trough will be, which will affect POPs
for the region early next week. With the exception of Saturday,
temperatures will generally run several degrees above average for
mid December, with highs in the upper 60s to low 70s and lows
generally in the 50s.


Winds and seas will decrease through sunrise, allowing the Small
Craft Advisory to expire later this morning. Winds will shift to the
west-southwest this afternoon, increasing to cautionary levels by
this evening and becoming more westerly overnight. Resultant seas
will range from 2 to 4 feet. Winds will diminish once again Friday
morning, with the next chance at elevated conditions coming Saturday
night into Sunday.


Afternoon relative humidity values will be less than 30 percent
today but light winds and low ERC values will preclude any red
flag products. Moisture increases beginning tonight.


Chances for showers will increase on Friday, mainly for coastal
locales, before increasing areawide late weekend into early next
week. Base on the current forecast, there are no concerns for
flooding associated with these systems. Rainfall totals through
the next week will generally remain below 1 inch.


Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.



Tallahassee   42  70  47  65  39 /   0   0  10  20  10
Panama City   50  70  51  62  41 /   0   0  10  20  10
Dothan        39  64  42  58  35 /   0   0   0  10  10
Albany        37  65  41  59  35 /   0   0   0  10  10
Valdosta      39  68  46  65  38 /   0   0   0  20  10
Cross City    41  72  50  72  43 /  20  10  20  30  10
Apalachicola  49  70  54  66  43 /  10  10  10  30  10


FL...High Rip Current Risk through late tonight for Coastal Bay-
     Coastal Gulf.



NEAR TERM...Harrigan
LONG TERM...Pullin
HYDROLOGY...Scholl is the U.S. government's official web portal to all federal, state and local government web resources and services.