Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
415 PM EST Fri Mar 6 2015
Near term [through tonight]...
Today was a tricky day in terms of forecast high temperatures. A
stubborn stratus deck below 925mb has been slow to erode. This deck
extends from the Atlantic west to Dothan then south to Blountstown,
and then east through Tallahassee and Cross City. Under this deck
temperatures have struggled to reach 50. As we move through the
evening hours, the deck should continue to erode as drier air is
slowly advected into the region.
The main forecast challenge for tonight is with low temperatures.
Compared to the previous cycle, min-temp guidance has nudged
upwards slightly so the minimum temperatures for tonight were adjusted
upwards. The main issue lies with upper level cloudiness. Some model
guidance indicates a moderate layer of cirrus moving from the
southwest into our forecast area. The degree in which we can attain
sufficient radiational cooling conditions is still uncertain.
Nonetheless most locations in southeast Alabama and northwest
Georgia should see freezing conditions while all other locations
should observe temperatures in the middle to upper 30s.
Short term [saturday through Sunday night]...
After a fairly chilly start to the day on Saturday with a light
freeze expected across the northwest 1/4 of the region, and a frost
advisory fcst for the remainder of our Georgia zones and many inland
portions of the Florida Panhandle, temps should recover fairly well under
plenty of sunshine on Saturday. High temps are expected to range
from the lower to middle 60s to the north, to the middle 60s to near
70 degrees south. With the gradually modifying sfc ridge nearly
overhead on Sat. Night, temps will still be fairly cool, with
overnight lows ranging from the middle 30s to the north and west to the
lower to middle 40s to the S and west. With plenty of sunshine and high
temps moderating to between 70 to 75 degrees in the afternoon,
Sunday should be ideal for outdoor activities, and may be the last
day without rain chances for quite some time. That said, as we move
further along in time on Sunday night, a warm front will be
developing across the northern Gulf of Mexico as an upper level trof
begins to dig southeast over Texas and the western Gulf. This developing
boundary will produce increasing rain chances from east to west across the
County Warning Area (20-40%) mainly after midnight.
Long term [monday through friday]...
While there are some differences between the 12 UTC GFS and ECMWF,
it appears as though our County Warning Area could be essentially "trapped" in a
corridor of moisture between the above mentioned upper low to the
west (which will be slow moving) and a fairly strong upper level
ridge for this time of year over the Bahamas. While a complete
washout is not anticipated at this time, and temps should be on the
warm side (especially further to the east where highs could approach
80 degrees on some days due to the lower pops and higher 500 mb
heights and 850 mb temps), each day will be marked by a chance of
rain. However, the potential threat for a heavy rainfall event
appears to be decreasing over time.
[through 18z saturday] a stratus deck roughly around 1-2000 feet has
been persistent all day at tlh, vld, and aby creating MVFR/IFR cigs.
As we move through the night this stratus deck should slowly erode
away from west to east, but the rate at which this happens is highly
uncertain. By 04z tomorrow all terminals should be at least VFR/MVFR
with VFR expected at all terminals by sunrise.
Although most areas over the coastal waters are just below headline
conditions as of 3 PM EST this afternoon, winds and seas will return
to cautionary level conditions very quickly this evening before
improving to below headline conditions by Saturday afternoon and
should remain below through the remainder of the weekend.
Minimum relative humidity values will approach or exceed red flag criteria tomorrow
afternoon. However, wind speeds around 5-10 mph, and durations less
than 2-3 hours, should be sufficient to prevent the issuance of any
red flag warnings in our County Warning Area.
There are currently no rivers in flood stage, while a few are still
in action stage. With no chances for rain over the next few days,
area rivers will continue to recede. At the beginning of the work
week chances for rain return, and thus a small increase in area
rivers could occur next week.
Preliminary point temps/pops...
Tallahassee 37 68 40 74 53 / 0 0 0 0 20
Panama City 41 64 46 68 54 / 0 0 0 0 30
Dothan 30 63 37 70 50 / 0 0 0 0 30
Albany 32 64 37 71 49 / 0 0 0 0 20
Valdosta 35 66 39 74 52 / 0 0 0 0 20
Cross City 40 69 43 75 56 / 10 0 10 10 20
Apalachicola 43 65 48 68 57 / 0 0 0 0 20
Florida...frost advisory from 4 am to 8 am CST Saturday for central Walton-
Freeze warning from 2 am to 8 am CST Saturday for Holmes-inland
Georgia...frost advisory from 5 am to 9 am EST Saturday for Baker-Ben Hill-
Freeze warning from 3 am to 9 am EST Saturday for Calhoun-Clay-
Alabama...freeze warning from 2 am to 8 am CST Saturday for Coffee-Dale-