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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
1007 am CDT Sat Jul 23 2016

Update...
morning satellite imagery and upper air analysis reveals sprawling
high pressure which extends from the Desert Southwest, eastward
into the southern Great Plains. A shortwave currently resides
along its eastern periphery--across the lower Tennessee Valley--
and this will begin to influence our weather in a more noticeable
way tomorrow and into Monday and Tuesday of the upcoming week.

Morning model guidance indicates a bit more moisture in the
925-700 mb layer will slosh into our eastern-most zones today with
mixing ratios increasing into the 11-13 g/kg range. Combined with
plenty of diabatic heating, this should be enough to spark off
some diurnally-driven storms this afternoon. Only anticipate
limited coverage given the degree of of subsidence still present
on the eastern fringes of the aformentioned high. That said, have
thrown in isolated thunderstorm wording (10-15% pops) this
afternoon east of a roughly Bonham to Palestine line.

Otherwise, another hot day is on tap with high temperatures
expected to top out once again near the century mark. May see some
heat index values approach 105-106 degrees this afternoon mainly
across our eastern zones, but as the previous shift mentioned,
these values will be short-lived as highs fall slightly tomorrow.

Carlaw

&&

Aviation...
/issued 617 am CDT Sat Jul 23 2016/
/12z tafs/

VFR conditions expected to prevail through the period with
southerly flow 10 kt or less. Isolated convection expected again
mainly in East Texas and should be of little impact to any North
Texas airports. No significant aviation concerns next 24 hours.

Dunn

&&

Previous discussion... /issued 411 am CDT Sat Jul 23 2016/
after another day or two of 100-degree heat, north and central
Texas's (relatively) brief flirtation with the century mark should
come to an end for several days. On the flip side, our rain
chances will creep upward, which should be welcome news for
everyone.

The large ridge draped across the central and western portions of
the country will hold sway again today, but weaken slightly and
recede westward by Monday. The key weather driver for our region
will be the approach - from the east - of a weak upper level
shortwave, now located over the lower Tennessee Valley. This
feature will slip westward along the southern rim of the upper
ridge, providing subtle lift over the area starting late Sunday,
and especially Monday and Tuesday. With the GFS and European model (ecmwf) both
advertising a marked increase in precipitable water, and together
with the sref, increased qpfs with the approach of this shortwave,
have included 30-40% pops over most of the eastern 2/3rds of
North Texas Monday and Tuesday. This shortwave should damp out and
move west of US by Wednesday, but the ongoing upper level easterly
flow pattern, together with increased moisture, justify at least
some low pops Wednesday.

By Thursday and Friday, the primary upper high should be well west
of Texas, leaving US in a weak northwesterly flow regime.
Attention from Thursday evening through Saturday may shift to our
northern counties, where convection may drift in from Oklahoma,
forced by multiple shortwaves that are dropping southeastward
through the Central Plains and mid-Mississippi Valley with the
main northern stream of the jet. Didn't go too crazy with pops in
this time horizon, but did include small chances near the Red
River. If a weak frontal or outflow boundary manages to enter
Oklahoma by the end of next week, it's certainly not out of the
question that extreme north central Texas could see some
thunderstorm activity - probably during the overnight hours.

On the temperature front, the persistent strength of the upper
ridge should facilitate 100-degree highs across much of north and
central Texas both today and Sunday. Increased moisture,
cloudcover, scattered rainfall, and modestly lower thicknesses
should all conspire to reel our highs back into the 90s starting
Monday, and continue all week. It's a tad premature to break out
the parkas, but seasonably normal readings in the mid to upper 90s
should be the norm.

Heat indices will probably climb into the 106-107 range in our
northeast counties today, and push 105 in many other locations.
These values will retreat on Sunday, and given the lack of
persistence, will forego a heat advisory at this time.

Bradshaw




&&



Preliminary point temps/pops...
Dallas-ft. Worth 100 80 99 79 96 / 5 10 10 10 30
Waco 101 78 100 77 97 / 5 5 10 10 30
Paris 99 77 98 76 94 / 10 10 20 20 40
Denton 100 77 98 76 95 / 5 5 10 10 30
McKinney 99 78 98 77 95 / 5 10 10 10 30
Dallas 100 81 99 80 96 / 5 10 10 10 30
Terrell 99 77 98 76 95 / 10 10 10 20 40
Corsicana 99 78 96 77 95 / 10 10 10 20 30
Temple 100 77 98 76 97 / 5 5 10 10 20
Mineral Wells 100 75 99 75 96 / 5 5 10 10 20

&&

Forward watches/warnings/advisories...
none.
&&

$$

30/90

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