Area Forecast Discussion
Issued by NWS Springfield, MO
FXUS63 KSGF 231734 AAB
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1134 AM CST Sun Nov 23 2014
...Updated Aviation Section...
Issued at 1041 AM CST SUN NOV 23 2014
Forecast updated to account for latest radar trends. Dry slot has
worked its way a little further east than originally anticipated,
shunting the best axis of rainfall across the eastern Ozarks. The
rest of the area remains under widespread stratus and patchy
drizzle. The storm system is maturing, thus the dry slot will
continue to work its way east heading into this afternoon. That
said, combination of upper support and mid level frontogenesis
will instigate a large area of light rainfall to our northwest.
This will shift southeastward into the area this afternoon
(getting as far south as a Rolla/Springfield/Cassville line). As a
result, rain chances will increase later this afternoon into this
evening for the northwest half of the area.
In addition, there short range models continue to suggest enough
MUCAPE to support a slight chance for thunder ahead of the
incoming cold front. The window of opportunity for thunder has
been contracted a bit, to mainly between 2 PM and 9 PM. The cold
front will make steady progress into the area into the overnight
hours, leading to a short window of opportunity for a brief period
of a rain/snow mix. We will be refining this risk with the
incoming 12z model output, but flakes will be possible
along/northwest of the I-44 corridor. Any accumulation may be a
bit tough as below freezing surface temperatures do not look to
arrive until after precipitation stops. That said, it will be
nighttime and a light dusting on grassy areas is not out of the
question in central Missouri.
Another thing to keep an eye out for this evening is winds.
Surface low pressure will ride northeast up the front as it moves
through the area this evening. The resultant increase in pressure
gradient will result in a period with sustained northwest winds of
25mph and gusts to around 40mph. Not quite getting to advisory
levels, but not far off either.
.SHORT TERM...(Today and Tonight)
Most locations remained dry overnight as a storm system continued
to approach the Ozarks region from the west. Eventually this
feature will force showers as early as this morning, and expand in
areal coverage throughout the day. We think most locations will
experience measurable rain this morning or this afternoon.
Perhaps better rain coverage will occur tonight as a cold front
sweeps through the area. There is a chance that some light snow
could mix with rain at times, particularly along and north of the
Interstate 44 corridor. The change over to some snow would not
occur until late in the evening or after midnight.
As of now we are not forecasting any accumulations, but the day
shift will need to take another look at this potential. The one
ingredient holding back slam dunk snow accumulation is
temperature, which may stay warm enough to mitigate
.LONG TERM...(Monday through Saturday)
Precipitation will exit the Ozarks early Monday morning, beginning
an extended period of dry weather.
Deep northwest flow will overcome much of the nation`s mid section
through the entire upcoming work week. This pattern will shut down
the Gulf of Mexico, while keeping temperatures slightly cooler
than normal for late November.
Look for temperatures in the 40s on an afternoon basis through
Saturday, with overnight lows in the 20s and 30s.
No precipitation is forecasted from Monday through Saturday.
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1134 AM CST SUN NOV 23 2014
Yet another complex and challenging forecast for area aerodromes.
Brunt of rainfall has shifted east of the aerodromes this morning
and for much of the afternoon, IFR stratus will lift to MVFR with
patchy drizzle around. Later this afternoon, the cold front to our
northwest will move into the region and increase rain chances from
northwest to southeast across the area. Still cannot rule out a
rumble or two of thunder from 21z to 03z along the front. Cold
front will arrive this evening at all TAF sites and winds will
abruptly shift to the west/northwest. Wind speeds and gusts will
be strong this evening and this will be something to monitor
closely. Rain will exit to the northeast after midnight. There
remains a brief window of opportunity for rain to mix with or
change over to snow. With temperatures in the mid 30s, impacts are
not expected. Stratus (IFR to low end MVFR) will linger into