Area Forecast Discussion
Issued by NWS Huntsville, AL

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FXUS64 KHUN 261925 CCA

Area Forecast Discussion...CORRECTED
National Weather Service Huntsville AL
225 PM CDT Wed Oct 26 2016

.NEAR TERM...(Rest of Today)
Issued at 849 AM CDT Wed Oct 26 2016

Visible imagery indicates a thin layer of low stratus has worked its
way into southeastern DeKalb County. Have updated the sky coverage in
this area for the next few hours, but fully expect this to dissipate
before Midday. The 12Z RAOB at BMX is slightly cooler than yesterday
at 850 mb, but given southerly flow and deep mixing expected again
today, have raised temps close to the max temps experienced on
Tuesday in the low to mid 80s in valley locations. Otherwise, no
other changes needed.

.SHORT TERM...(Thursday through Friday)
Issued at 207 PM CDT Wed Oct 26 2016

Short range models continue to indicate a narrow corridor of moisture
transport and PW increase which generates -shra later tonight into
Thursday morning. This corridor develops across eastern MS and
western AL spreading northeast through northern AL into southern
middle TN Thursday morning as an upper trof approaches. The NAM and
GFS both generate modest CAPE values of 500-1000 j/kg on Thursday, so
am hesitant to remove thunderstorms. However, the slight chance POP
looks good at this point, especially on Thursday as the upper level
support wanes.

A cold front will be lagging behind as has been indicated in
previous model runs. The front slowly aligns itself in a more east-west
fashion and may reach the AL/TN border Thursday Night before stalling
out and/or dissolving. Little airmass change for our area is now
foreseen through this process, although slightly drier air may
advect into our eastern counties equating to cooler overnight lows
than further west. This has been played out in our forecast grids
over the weekend.

.LONG TERM...(Friday night through Tuesday)
Issued at 207 PM CDT Wed Oct 26 2016

Besides a dry and weak 500 mb shortwave on Sunday, rather persistent
mid to upper level ridging (particularly at 850-700 mb) will be
sprawled out from the southern Plains east along the Gulf Coast. This
equates to another dry forecast. By days 6-7, the 850 mb high will
be centered just about on top of our forecast area. Temps will be
rather unchanged during this period as well, with 850 mb values of
~14-16C. Given the past few days temps based on 850 mb temps and
adequate mixing (much like yesterday), max temps should easily reach
the lower to middle 80s, if not a bit higher as indicated by the
ECMWF MOS forecast. Will likely go above suggested blends siding
closer to the warmer ECMWF. The following all-time November record
highs may be at risk:

HSV 84 in 2012
MSL 86 in 1915


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1124 AM CDT Wed Oct 26 2016

VFR flight weather conditions are anticipated during the next 24
hours, outside of any shower activity that develops late tonight. The
probability of this occurrence remains too low to include in the
TAFs. CIGs aoa 050AGL are expected to develop by 06-08Z as southerly
flow increases moisture in advance of an upper level trof axis. The
clouds will linger through midday Thursday before the trof exits to
the southeast.





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