Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
1046 am EDT Wednesday Jun 3 2015
Near term [through today]...
The upper low is now centered over the southern Appalachians near
the Tennessee/NC border. Water vapor imagery indicates that quite a bit
of middle/upper level dry air has rotated into the area on the south
side of this low. The 12z ktae sounding shows the precipitable water down to
1.31. Inches. The position of the upper trough puts US in a dnva
scenario today, so there will be less qg forcing to aid ascent.
Therefore the sea breeze should be the primary trigger across most
of the forecast area. We are in a favorable low-middle level flow
regime. There is also a stalled frontal boundary over southeast Alabama
that could focus convection in that area. Probability of precipitation were adjusted a bit
to blend in the latest ecam probability of precipitation. Temperatures were also bumped up about
a degree base Don morning trends. Once again, we find a portion of
the forecast area in a marginal Storm Prediction Center risk for severe storms. We
feel the most likely area for severe today will be across our Georgia
zones, with gusty winds the main threat. Small hail will also be
possible, but severe-size hail will mainly be north of the
Previous discussion [630 am edt]...
Short term [tonight through friday]...
Low-middle level flow will shift to a north-northeast direction for
this part of the forecast period. This tends to favor more
limited convective coverage that is concentrated primarily south
of Interstate 10, and a few isolated storms offshore overnight,
during our sea breeze convection season. That is generally the
template that we followed for the pop forecast. The middle-upper
level low will slowly lift east-northeast to coastal North Carolina through
the period, which will place our area in a region of neutral to
negative upward vertical velocity - meaning the added large scale support for
convection we saw a couple days ago will be absent. All of these
signals, in addition to below normal precipitable water, indicate
more isolated storms for Thursday and Friday. High temperatures
will likely reach into the lower 90s in many areas, with lows
around 70 degrees.
Long term [friday night through wednesday]...
The north-northeast flow at low levels should continue through the weekend
before beginning to pivot back around to a more southerly
direction early next week. This should lead to a continuation of
isolated storms through the weekend, with a gradual increase in
probability of precipitation possible early next week. Highs will be in the lower 90s and
lows in the lower 70s which will be slightly above normal.
[through 12z thursday] patchy low ceilings across the area will dissipate
within a few hours of sunrise. In the late morning-early afternoon,
thunderstorms will begin to spread inland from the coastline. Tlh
and vld are the terminals most likely to be affected directly by
thunderstorms with gusty winds possible. Outside of thunderstorms,
winds will be light and variable.
Light and variable winds will keep seas 1 foot or less through the
period. Isolated to scattered showers and storms are expected as
well, which may produce some locally higher winds and waves.
A warm, moist air mass typical of summertime will prevent US from
reaching critical fire conditions.
The Choctawhatchee River at Bruce was the only river at local
action stage, and it's forecast to remain at a broad crest the
next few days before slowly falling late this week. Although
isolated heavy rain amounts are possible, we do not expect rain
over the next several days to be concentrated enough to cause
widespread flash flooding or river flooding.
Preliminary point temps/pops...
Tallahassee 90 69 92 70 91 / 50 30 30 20 30
Panama City 86 73 85 73 86 / 40 20 30 20 30
Dothan 89 69 90 69 89 / 50 30 20 10 20
Albany 90 68 89 69 90 / 60 40 20 10 20
Valdosta 89 68 91 68 90 / 60 50 40 20 30
Cross City 90 67 91 69 91 / 30 30 30 20 30
Apalachicola 86 72 86 73 86 / 30 20 30 20 30