Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
1135 PM CDT Wednesday may 27 2015
Updated for the 06z aviation discussion
Previous discussion... /issued 920 PM CDT Wednesday may 27 2015/
Large area of rain over NE MS will continue to slowly move off
into northern Alabama over the next couple of hours. Some convection is
firing along the stationary front over southern MO...just north of the
area. This activity will most likely stay to the north but will
leave a small pop along the northern tier just in case. Meanwhile the
remainder of the midsouth is quiet with just some high clouds.
Most areas received some rain today. This combined with some
clearing and light winds should result in at least patchy fog by
morning. Update already out.
Previous discussion... /issued 303 PM CDT Wednesday may 27 2015/
We remain in a very messy pattern wherein the smallest of
features play big roles in the strength of storms. The good news
is that rain and clouds will keep temperatures down and our lawn
and gardens watered. However it does come with a price...see
Brookland Arkansas for an example. Heavy rain...up to three
inches...produced quite a bit of flash flooding there today.
Not a lot is expected to change synoptically over the next few
days. Temperatures should trend slightly warmer tomorrow and
Friday...but over the weekend...a broad trough will shift out of
the plains resulting in thickness falls...and cooling
temperatures. The warmest day should be Friday when highs should
be solidly in the middle 80s area wide. Expect low to middle 80s
each day for the remainder of the forecast period. Lows will be in
the upper 60s to near 70 degrees.
As a weak shortwave ridge shifts across the midsouth tomorrow and
Friday...the potential for wet microbursts will increase. Precipitable waters
will increase to between 1.5 and 1.75 inches so the threat of
localized flash flooding will also continue...if not increase.
Saturday and Sunday a trough will dig into the Southern Plains
strengthening the southerly flow over the area. Storms should
become more progressive and subtle disturbances moving through
the mean flow will play major roles in precipitation each
period...much like we saw yesterday and today.
Both the GFS and the European model (ecmwf) have a cutoff low parked near or just
west of the midsouth Monday through midweek...if this scenario
pans out...we may need to lower temperatures slightly during the
period...but readings should still remain near to slightly below
06z taf cycle
VFR conditions will persist for most of the forecast period. Some
fog is expected to develop overnight and could get dense in some
areas. Along with the fog could be some low clouds producing LIFR
ceilings at times around sunrise. Scattered thunderstorms may
develop mainly during the afternoon hours with northeast Mississippi
having the best chance. Winds will be light and mainly from the
south during the forecast period.