Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Mobile Alabama
932 PM CDT Friday Aug 28 2015
Update...have gone with slight chance to chance probability of precipitation for the
remainder of the night for much of the area except for southeast
Mississippi due to lingering convection which will gradually weaken
overnight. Made other minor adjustments. /29
Previous discussion... /issued 558 PM CDT Friday Aug 28 2015/
00z issuance...VFR conditions continue for the next 24 hours with
southerly winds near 4-6 knots becoming light this evening then
increasing to near 8 knots by midday Saturday. /29
Previous discussion... /issued 344 PM CDT Friday Aug 28 2015/
Short term [tonight through Sunday night]...tonight through
Saturday...an upper low over the forecast area meanders around over the area for
the first 24hrs of the forecast. A surface ridge stretches west over
the eastern Seaboard...pumping in moisture off the tropical
Atlantic...and when combined with a shortwave swirling around the
east side of the upper low...rain expected over the forecast area will be
inconsistent. Eastern portions of the forecast area are expected to see the best
coverage of rain...and with this...the coolest temperatures on Saturday.
Western portions of the forecast area will see significantly smaller chances of
rain...with temperatures closer to seasonal.
Saturday night through Sunday night...an upper ridge stretching west
over the western Atlantic to over the southeastern Atlantic Seaboard
hangs tough...and if anything...builds west a bit. The upper low over
the Continental U.S. Opens...with the mean trough it is sitting in shifting
west...to over the OK/TX/AR/la area before organizing into another
closed low. With the ridge becoming more in control of the weather
over the forecast area...the chance of rain decreases...with temperatures rising to a
bit above seasonal. Moisture levels remain high (1.5-1.9" depending
upon the model)...so heat indices rise to the upper 90s for Sunday.
Chance of rain still remains highest over eastern portions of the forecast area.
Erika starts to move north along the West Coast of the Florida
Peninsula...and begins to make itself known with the east to
southeast low level flow becoming more northeast to east.
Long term [monday on]...(no updates from previous shift) the
National Hurricane Center has tropical cyclone Erika moving north-
northwest over the southern Florida Peninsula on Monday...and over
the northern Florida Peninsula on Tuesday. If the forecast track
keeps Erika to our east...a gradual decrease in moisture through the
remainder of the long term is expected as winds turn back to a
northern flow. Subsidence along the western periphery of Erika will
also cut down our rain chances. For now have isolated showers and
thunderstorms southeast of I-65 on Monday...with no rain to the
northwest of I-65. Isolated to low end scattered showers and
thunderstorms are expected through the remainder of the long
term...mainly during the daytime hours. High temperatures will still
manage to reach the lower 90s each day inland areas...with upper 80s
along the immediate coastal sections. /22
Marine...surface high pressure moves east into the Appalachians
this weekend...resulting in the development of a light onshore flow.
The surface high remains in place into the first half of next week.
Little change in seas. Meanwhile...Erika is forecast by the National
Hurricane Center to approach the southern tip of Florida by late
Sunday night and lift north northwest across the western Florida
Peninsula on Monday.
Preliminary point temps/pops...
Mobile 68 87 70 90 70 / 10 20 20 20 20
Pensacola 72 85 72 89 73 / 30 50 30 30 20
Destin 76 82 74 89 75 / 30 60 20 30 30
Evergreen 67 87 69 90 68 / 30 50 30 30 20
Waynesboro 66 87 66 90 68 / 10 20 20 20 10
Camden 68 87 68 90 68 / 30 50 30 30 20
Crestview 69 85 69 91 68 / 30 60 30 30 20