Area Forecast Discussion
Issued by NWS Huntsville, AL

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FXUS64 KHUN 101829

Area Forecast Discussion
National Weather Service Huntsville AL
129 PM CDT Mon May 10 2021

.NEAR TERM...(Tonight)
Issued at 129 PM CDT Mon May 10 2021

A cold front continues to shift south of the area this afternoon. Low
clouds, mist and fog have persisted atop the higher Plateaus thus
far, especially in our southeastern counties. Further north, a few
thin spots have occurred where stratus has become more cellular in
nature. That should continue to be the trend as we head into the
early evening, with thicker clouds south, and a few patches of
clearing north. This will allow temperatures to dip into the upper
40s north, with lower to middle 50s south overnight. Zonal flow will
persist with isentropic lift and rainfall developing across southern
AR into central or northern MS late tonight, possibly spreading into
central and north AL late tonight. The NAM is most aggressive with
this, while the GFS is far less so. Will keep the PoP very low as a
result, mainly in our southwestern counties.

.SHORT TERM...(Tuesday through Wednesday)
Issued at 129 PM CDT Mon May 10 2021

With the frontal zonal at the surface pushing into far southern MS
and AL, most of the deep convection will remain well south of our
area. Elevated convection may reach north into central AL, and
perhaps our far southern counties, but most of our rain should remain
showers or even stratiform in nature. This is also confirmed by
various HREF solutions as well. The clouds and rain will keep
temperatures on the cool side with highs only in the upper 60s to
around 70. And this may be optimistic if the rain is more widespread
than forecast. Most of the rain will remain in north AL, with a
slight chance or lower in southern middle TN.

The models show area of showers/rain lifting northward Tuesday
evening, spread north by the strong MCS expected in south AL. We will
keep PoPs in the low to mid chance range for now, but may need to
increase this if model consistency continues. Rain could linger into
Wednesday, but there is model support that dries us out (expect for
more low clouds), so will keep a low PoP in for now. Total rain
amounts of 0.25-0.5 inch are expected in north AL with less than
0.25 inch in southern TN.

.LONG TERM...(Wednesday night through Sunday)
Issued at 129 PM CDT Mon May 10 2021

The low level convergence axis responsible for most of our rainfall
early this week pushes to our south Wednesday night. Early Thursday,
a surface low pressure system over the Gulf of Mexico will send an
additional plume of moisture into the TN Valley ahead of an
approaching shortwave trough. This will provide just enough moisture
for another round of showers Thursday morning, with scattered
coverage focused along a surface trough axis. Rain will taper off
Thursday evening as the low and shortwave trough push eastward.
Starting Friday, surface high pressure and ridging aloft advance into
the Southeast. As a result, look for a warming trend as highs
stretch from the mid to upper 60s on Thursday into the low 80s by
Sunday with mostly clear skies.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 11251 AM CDT Mon May 10 2021

Ceilings will slowly lift from ~010agl to ~020agl through 21Z.
Ceilings will likely remain MVFR through the rest of the period in
the 020-030agl range. North flow of 4-7kt will become northeast late
tonight into early Tuesday.





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