Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Memphis Tennessee
1144 PM CDT Sat Jul 30 2016
06z aviation discussion update.
Previous discussion... /issued 902 PM CDT Sat Jul 30 2016/
updated to increase evening pops across portions of north
radar continues to show area of thunderstorms holding together in
Coahoma County. This activity will track east over the next two
hours before the northern fringe begins dissipating. Pockets of
heavy rainfall can be expected over Coahoma and Tallahatchie
counties. In addition...short term models suggest activity
developing after 3 am in southeast Missouri and northeast
Arkansas. Have adjusted the overnight forecast accordingly.
Previous discussion... /issued 345 PM CDT Sat Jul 30 2016/
as of 3pm, temperatures throughout the mid- south are slightly
below normal but humidity values in the low to mid 70s still make
it seem quite uncomfortable outside. The mid- south is currently
free of thunderstorms but a few strong discrete cells currently
over central Arkansas continue to slowly move eastward towards the
area. Short term models including the hrrr and rap, have not
picked up on this feature. However, it's hard to believe in a
solution where these storms don't impact at least the western
counties of our warning area this afternoon before they fall
apart. The main threats with any storms this afternoon will be
straight line wind damage.
Short term...tonight through Monday.
There will be a slight chance of thunderstorms tonight throughout
the mid-south as a weak upper level shortwave moves through the
region. Slightly warmer conditions are expected on Sunday. The
warmer temperatures coupled with increased low level moisture
could lead to heat index values near 100 degrees. More afternoon
thunderstorms are also expected tomorrow as another shortwave
disturbance embedded in upper northwest flow aloft moves through the
mid-MS valley. Strong storms will be possible with straight line
winds remaining as the primary threat. Upper level heights will
continue to build over the plains on Sunday and by Monday the mid-
south will be on the eastern periphery of a steep upper level
ridge. This will result in warmer temperatures and more diurnally
driven thunderstorms Monday.
Long term...Tuesday through next weekend.
A warm start to August is expected for the mid-south. Models
agree on a broad upper ridge building and remaining parked over
the central U.S. Throughout most of the upcoming work week. High
temperatures will range from the low to mid 90's throughout the
work week. Southerly flow near the surface will result in humid
conditions. Heat indices will flirt with heat advisory criteria
from Tuesday through at least Friday. Diurnally driven
thunderstorms will be possible each day. Further out in the
Atlantic Ocean, the NHC has given a tropical wave a 60% chance of
developing into a tropical cyclone over the next 5 days.
06z taf set
VFR conditions should prevail through the forecast period. Additional
storms may develop prior to sunrise around kjbr and spread
southeast through the day with additional development. Timing of
convection has been notoriously difficult in northwest flow aloft
and subtle disturbances embedded within the flow. Although there
will likely be higher chances at times during the
period...confidence remains too low to include anything more than
thunderstorms in the vicinity at this time.
Winds should remain light through the forecast period.