Area Forecast Discussion
Issued by NWS Huntsville, AL

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FXUS64 KHUN 271723

Area Forecast Discussion
National Weather Service Huntsville AL
1223 PM CDT Thu Apr 27 2017

For 18Z TAFS.


.NEAR TERM...(Rest of Today)
Issued at 942 AM CDT Thu Apr 27 2017

Isolated showers over the far eastern portion of the forecast area
are all that remain from the convection that moved through early this
morning. These showers will push east of the area over the next hour
as a cold front continues to move through the region. This front was
extending from NW Indiana, almost due south through western Alabama.
Behind the front, extensive cloud cover was observed from satellite
imagery and surface observations, extending to the MS River.
Although some areas have cleared out a bit, these clouds will settle
in as the front moves east and most of the TN Valley will see mostly
cloudy skies through at least noon.

The front is expected to move east of the forecast area by 18Z, with
clouds lingering across the east through mid afternoon. The
combination of the cloud cover and CAA at the surface will keep
temperatures from warming up too much. Current temperatures in the
lower to mid 60s will only reach into the low to mid 70s by this
afternoon. Expect skies to become mostly clear across the area by
sunset. No major changes were made to the previous forecast.

.SHORT TERM...(Tonight through Saturday)
Issued at 405 AM CDT Thu Apr 27 2017

A weak area of high pressure out of the srn Plains states will then
quickly move ewd across the region tonight, with low clouds returning
from the sw going into the early morning hrs Fri. With the sfc high
draped across the srn Atlantic states on Fri, return/sly flow will
quickly become established over the region, thereby allowing the
previous cold front to double back to the n as a warm front well
into the afternoon period. This may result in a few showers/tstms
along the passage of the warm front heading into the evening hrs. The
sly flow will also usher warmer air back into the cntrl TN Valley,
with highs on Fri climbing back into the lower/mid 80s for most
locations. Isolated showers/tstms will remain in the forecast for the
first half of the weekend period, as weak upper disturbances
traverse newd over the region in response to an amplifying upper
low/trough pattern over the cntrl/srn Plains.

.LONG TERM...(Saturday night through Wednesday)
Issued at 405 AM CDT Thu Apr 27 2017

The focus of this morning`s forecast package then shifts toward the
Sun/Sun night time frame, as the upper low/trough axis over the
Plains states begins to lift ne into the Great Lakes region. The
latter half of the global models are also pointing to an associated
sfc low pushing into the Great Lakes states while an attendant cold
front stretches swd into the nw Gulf. This sfc boundary should begin
to translate ewd into the Mid South/Lower MS Valley early Sun. The
00Z GFS/ECMWF are hinting at a line of strong/svr tstms developing
along/ahead of the front as it moves ewd into the mid TN Valley. Low
level curvature/shear values, coupled with increasing buoyancy/lift,
all suggest the potential for damaging winds and large hail embedded
within bowing segments of the line of tstms as it moves ewd across
the area Sun afternoon/evening. The tstm threat should then come to
an end Mon morning with the passage of the cold front to the e.

Relatively quiet and seasonable conditions are then xpcted on Tue as
high pressure once again quickly moves ewd across the region in the
wake of the frontal passage. Showers/tstms then return to end the
forecast period, as another developing storm system over the cntrl
Plains states begins to translate ewd.


.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1223 PM CDT Thu Apr 27 2017

MVFR cigs will remain over the KMSL terminal through 20Z. Skies will
then clear, leaving VFR conditions at KMSL and KHSV through much of
the period. There is a low chance that the low cigs will move back
into KHSV, however confidence is low. Winds will also be gusty at
times this afternoon and then become light and variable around
sunset. A warm front will lift northward during the early morning
hours on Friday, and winds will shift to the south between 13Z and
14Z. MVFR cigs will move in behind the warm front and linger through
the end of the period. There may be isolated convection as well,
however coverage and confidence is too low to mention in the TAFs.





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