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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
555 PM CST Mon Dec 5 2016

/00z tafs/

Evening satellite and radar imagery from across the region shows a
continued eastward trend in precipitation and cloud cover as the
main upper low moves off to the northeast. However...despite the
upper trough pulling away...the surface cold front lags well
behind. This will result in low level moisture remaining in place
across North Texas through tonight. With a weak surface low
expected to be very near the metroplex during the overnight
hours...conditions will become very favorable for extensive low
cloud cover and fog. For the metroplex tafs...will start the
period with MVFR cigs and some light rain...but this rain should
move to the east within a few hours. As it does...VFR conditions
will likely prevail for several hour as drier air moves in aloft.
After midnight the boundary layer cools
further...extensive reduction in visibility is expected with
fog and very low clouds. Will show IFR cigs by 1 am with further
reductions through early Tuesday morning. There could be a few
hours where extensive dense fog reduces visibility to 1/2 mile or
less. As the cold front moves through during the morning hours on
Tuesday...northerly winds will increase and will likely clear the
fog resulting in low cigs for several hours. By afternoon...cigs
will continue to lift with MVFR conditions expected through

At Waco...similar trends are expected...although VFR conditions
may not be as long lasting later this evening. Similar timing on
the reductions to vis/cigs are expected with improving conditions
during the mid/late morning hours on Tuesday.



Previous discussion... /issued 352 PM CST Mon Dec 5 2016/
the upper low responsible for our recent bout of rainy weather is
churning east through the Texas Hill country and will skirt our
southeastern zones this evening. Its final round of light rain
took the better part of the day to reach areas along and north of
the I-20 corridor, but Dallas/Fort Worth and Sherman/Denison are
now experiencing the wet afternoon commute that was expected.
Additional rainfall entering central Texas will spread north
across the area into the evening hours. The last spits of rain
will gradually shift east as the low departs, and the showery
convection will be confined to East Texas by midnight.

Some clearing will encroach from the southwest after nightfall,
but as the nocturnal boundary layer cools, this will steadily be
replaced by fog. On the back side of the departing upper low,
north winds will usher in cooler air in the northwest, but the dry
advection will lag behind. The result will be fog and drizzle that
will eventually shift south as drier air filters in after daybreak
Tuesday. Even if there are peaks of sun on Tuesday, the cold
advection should keep temperatures generally in the 50s. The
exception would be southern and southeastern zones where the
cooler air will take longer to arrive.

Clouds will keep temperatures in the 40s across much of the region
Tuesday night. But in our northwestern zones, where winds will be
light and skies may clear, the Mercury may dip to near freezing
Wednesday morning. Afternoon temperatures will be near seasonal
normals on Wednesday, but an Arctic front will arrive late in the
day. Temperatures will plummet Wednesday night will blustery north
winds. Wind chills will be in the teens for the Thursday morning
commute, and those who have to be outdoors should plan
accordingly. Although the sun will come out on Thursday, afternoon
temperatures will be in the 30s with a biting wind.

With clear skies, light winds, and skin-cracking dew points in the
teens, radiational cooling will be in full force Thursday night.
Friday morning will be the coldest morning since the winter of
2014-2015 with much of the region seeing temperatures in the
teens. The current forecast low temperature at dfw Airport and
Waco is 20 degrees. If either site dips into the teens, it would
be the first occurrence since January 2015. That was also the most
recent teens for Sherman/Denison, where the forecast low Friday
morning is 18 degrees. A sunny day with light winds will follow,
but temperatures will only peak in the 40s. A warming trend this
weekend will push temperatures into the 50s Saturday afternoon and
the 60s Sunday and Monday next week.



Preliminary point temps/pops...
Dallas-ft. Worth 44 55 41 56 29 / 30 10 5 10 10
Waco 42 56 41 60 32 / 20 10 5 10 10
Paris 42 53 39 51 27 / 70 10 5 20 10
Denton 40 53 37 54 26 / 30 10 5 10 10
McKinney 40 53 39 54 28 / 40 10 5 10 10
Dallas 44 54 42 56 30 / 40 10 5 10 10
Terrell 42 56 41 56 30 / 40 10 5 10 20
Corsicana 43 59 44 58 33 / 40 10 5 10 20
Temple 43 58 43 60 33 / 20 10 5 10 10
Mineral Wells 40 51 35 55 27 / 10 10 5 5 10


Forward watches/warnings/advisories...


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