Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Birmingham Alabama
333 am CDT Sat Jul 4 2015
through 12z Monday.
Radar imagery is very similar to this time yesterday morning...
with a persistent corridor of showers and storms extending
across the northern part of the County Warning Area and westward into Arkansas.
The forecast area is positioned ahead of a slow-moving positively
tilted 500mb trough axis. High precipitable water values and unidirectional
westerly flow will continue to support multiple rounds of
thunderstorm activity through Sunday morning mainly across the
northern half of the County Warning Area...and a Flash Flood Watch has been
issued for those areas. Very heavy rainfall upstream across
Mississippi is on a trajectory toward Marion County...where
rainfall estimates are approaching 10 inches since July 1st. Very
saturated ground exists in the Flash Flood Watch area...and flash
flooding could become a significant issue later this morning.
Farther south...additional thunderstorm activity is expected as
daytime heating occurs. 700-500mb flow of 30-40kt will support
bowing segments and a potential for isolated damaging wind mainly
this afternoon and evening...similar to what occurred yesterday.
The southern end of the upper-level trough is expected to amplify
tonight and become nearly closed off Sunday morning as it moves
slowly across Tennessee. With a lack of ridging upstream from the
trough...precipitable water values should remain quite high near and behind the
through axis. Have raised probability of precipitation across the entire County Warning Area for Sunday...
and cannot rule out a need for the Flash Flood Watch to be
extended in time and/or expanded southward.
after 12z Monday.
The trough finally begins to exit on Monday as a cold front tries
to swing down toward the area. However it looks like the Bermuda
ridge will build into the area and keep the front from working
into the area and eventually push it back north by Thursday or
Friday. With that scenario precipitation chances will drop
significantly Tuesday/Wednesday as the high pressure tries to
build into the area. Looks like we do get back to more of a
climatological Summer by Wednesday/Thursday with highs back in the
upper 80s north to low 90s south and isolated/scattered showers
storms in the peak heating of the day.
06z taf discussion.
Showers and storms moving from west to east across central
Alabama will pose a threat the next few hours. The main activity
the next couple of hours will be approaching mgm. In short...
potential impacts possible at anytime this overnight with
storms/showers and MVFR ceilings. Winds generally south to
southwest at 4 to 8 kts. Additional showers and storms possible
in the afternoon.
High humidity values and above normal rain chances will continue
for the next few days. There are no fire weather concerns.
Preliminary point temps/pops...
Gadsden 82 69 83 68 86 / 80 50 60 30 50
Anniston 84 69 83 68 86 / 70 60 60 30 50
Birmingham 83 70 84 70 86 / 80 60 60 30 50
Tuscaloosa 85 71 87 70 89 / 80 60 60 30 50
Calera 85 70 85 70 86 / 70 60 60 30 50
Auburn 86 70 85 70 85 / 50 60 50 30 60
Montgomery 90 72 87 71 88 / 60 60 60 30 60
Troy 90 71 88 70 88 / 50 60 50 30 70
Flash Flood Watch through Sunday morning for Blount-Calhoun-