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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
654 am CDT Monday may 25 2015

Aviation...
/12z tafs/

Challenges are similar to previous days regarding timing flight
conditions each morning and overnight...along with convective
trends.

The next shortwave disturbance aloft is now lifting over SW Texas
as evident by the increasing strong-severe thunderstorms and rain from kmaf to kdrt
at sunrise. High res models agree on a linear or qlcs type of
complex driven by large-scale ascent and speed of the progressive
shortwave. Have only made minor tweaks to timing convection into
the terminals in the 17z-18z time frame with best window for
IFR/thunderstorms and rain conditions west/heavy rain occurring through 21z-22z. The
longer window is in case secondary development occurs on a surging
drying into western North Texas by middle afternoon.

MVFR conditions will prevail with tempo IFR/-dz through middle morning.
As lift and mixing increase after 18z...expect prevailing low VFR
with occasional MVFR with thunderstorms and rain. VFR will hold on through at least
middle evening before MVFR arrives back in around midnight. More IFR
possible just before daybreak Tuesday.

South-southeast winds 10-15 kts winds will prevail through the forecast...with
occasional variable higher wind gusts in and near convection this
afternoon.

05/

&&



Previous discussion... /issued 326 am CDT Monday may 25 2015/
a shortwave trough currently near El Paso is prognosticated to move east
into central Texas during the day today...providing our next
opportunity for convective weather following a short reprieve
overnight. Strong ascent will spread east into the central part of
the state over the next few hours...which should lead to shower
and thunderstorm development west of our County Warning Area. Hi-res model data
suggests that this activity will develop east into our western
counties this afternoon. The time of day should ensure maximum
instability as lift spreads overhead later today. SBCAPE in the
range of 2000-4000 j/kg will be sufficient when combined with
marginal bulk shear values to generate strong to severe storms
this afternoon...with large hail...damaging winds and a few
tornadoes all possible.

Moisture profiles are not as impressive as what we experienced
during the Saturday night/Sunday event. However...respectable
precipitable waters of around 1.5 inches will still be plenty high for locally
heavy rain...and the Flash Flood Watch will remain in effect
through this evening. Fortunately...this system is pretty
progressive and should accelerate off to the northeast during the
evening hours...ending precipitation chances from west to east
tonight.

The latest model projections indicate that a subtle upper trough
will linger overhead Tuesday following the exit of today/S fast
moving shortwave. This pattern will set US up with the potential
for more severe weather Tuesday afternoon and evening. Good
surface heating is expected to occur area-wide as a dryline
surges east near the western County Warning Area border. We have gone with highs
around 90 across the west and the middle 80s elsewhere. Overall
forcing associated with the trough will be fairly weak...so
thunderstorm coverage may not become particularly high.
However...good moisture and impressive instability values will
ensure that just about any storm which develops will become
severe. For now we will keep 30 probability of precipitation over the west and slight
chance elsewhere.

A shortwave ridge will develop overhead on Wednesday as the
trough shifts east of the region...bringing a lull in
precipitation chances midweek. Good moisture and strong lift will
bring rain chances back to the region Thursday and Friday as yet
another upper trough propagates east from the West Coast into
West Texas. This trough will then slow down...broaden and linger
across the Southern Plains...providing a good chance of showers
and storms through the weekend...and possibly even into next
Monday. Another break in the precipitation looks possible Tuesday
and Wednesday of next week as the upper trough shifts east and an
upper ridge develops overhead.

30

&&




Preliminary point temps/pops...
Dallas-ft. Worth, Texas 81 66 87 70 85 / 70 40 20 30 20
Waco, Texas 84 67 86 71 86 / 90 30 20 20 20
Paris, Texas 77 65 82 68 85 / 70 60 20 20 20
Denton, Texas 79 64 86 69 86 / 70 40 20 30 20
McKinney, Texas 81 65 84 69 86 / 70 50 20 30 20
Dallas, Texas 83 66 86 71 87 / 70 50 20 30 20
Terrell, Texas 83 66 85 71 88 / 80 50 20 20 20
Corsicana, Texas 81 67 85 72 86 / 90 50 20 20 20
Temple, Texas 82 67 87 70 88 / 90 30 20 20 20
Mineral Wells, Texas 77 64 88 69 86 / 70 20 30 30 20

&&

Forward watches/warnings/advisories...
Flash Flood Watch through this evening for txz091>095-100>107-
115>123-129>135-141>148-156>162-174-175.



&&

$$

05/30

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