Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus64 khun 160026 

Area forecast discussion
National Weather Service Huntsville Alabama
626 PM CST Fri Nov 15 2019

for 00z tafs.


Near term...(tonight)
issued at 250 PM CST Fri Nov 15 2019

A complex setup was present across the region this afternoon. Effects
from a surface low deepening off of the South Carolina coast extended
to the west. The western extent of this system (especially below
500mb) was inducing upglide and producing light rain from parts of NE
Alabama southward to the Florida Panhandle. The strongest ascent
near/south of I-20 and east of I-65 was where the lion's share of the
rain was occurring. More lift to our south and resultant clouds have
made for more clouds than sun for most of the forecast area. Only
far northwest Alabama further northwest of the system was experiencing mostly sunny
skies. Despite the sun, cold air advection on the western periphery
of this system has helped keep air temperatures on the cool side,
ranging in the upper 40s to mid 50s.

Short term model output was in reasonably good agreement regarding
the development of this system. Rain over and south of the area
should slowly advance eastward this evening. Went on a slower track
than the hi-resolution models showed, ending rain over NE Alabama in the
early evening. As cold air advection and skies clear, another chilly
night with lows cooling into upper 20s to around 30, with northerly
winds of 5-10 mph.

Short term...(saturday through monday)
issued at 250 PM CST Fri Nov 15 2019

Dry conditions and cooler than normal temperatures should continue
over the weekend into early next week. The storm forming off the
coastal Carolinas will be moving slow to the north and east, its
movement caused by cold high pressure moving from south central
Canada to the Maritimes by Sunday evening. Cold air associated with
this ridge will extend well the south and southwest. Thus high temps
on Saturday will rise into the low/mid 50s. Normal highs this time of
year are around 63 degrees. Lows will cool to around 30 for Sat
night. A tad warmer, with highs in the upper 50s under partly cloudy
skies on Sunday.

In a stormy polar jet, another disturbance will move towards the area
on Mon. The models for the most part stayed dry, however the European model (ecmwf)
was hinting at light rain. Stayed with a dry trend, but did continue
a mostly cloudy to cloudy trend day. The clouds and passing of a weak
frontal boundary will make for a cool start for a new work week,
with highs in the low/mid 50s.

Long term...(monday night through thursday)
issued at 250 PM CST Fri Nov 15 2019

The first half of next week, an upper-level trough sits over the
eastern Continental U.S.. though precip stays well to our north, this will keep
cloud cover over the Tennessee Valley. This will keep temperatures
below normal through Tuesday. This trough finally exits the region
late Tuesday and an upper-level ridge starts to build on Wednesday.
This will bring temperatures back up into the 60s Wednesday for the
first time in what feels like a while. An approaching trough will
bring more rain later next week. A lot of uncertainty still exists in
this system late next week, but both the GFS and European model (ecmwf) are in fairly
good agreement on the system bringing rain sometime in the
Thursday/Friday timeframe.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 626 PM CST Fri Nov 15 2019

VFR/sky clear will be the prevalent condition at the terminals from this
evening thru early Sat morning, as mid/high-level cloudiness
associated with an upper low moves southeastward and away from the
region. However, as the upper low shifts further eastward overnight
and winds aloft back to the northwest, sct cirroform clouds may begin
to spread southeastward into the region shortly before 12z. Sfc flow
will remain from the north-northeast thru the taf period, with speeds of 5-10
knots overnight diminishing during the aftn. Although some patchy fog
will be possible in wind-protected valley locations btwn 16/08-13z,
confidence is too low to include vsby reductions in the forecast at
this point.


Hun watches/warnings/advisories...



Near term...rsb
short term...rsb
long term...McCoy

National Weather Service Glossary of Abbreviations