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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
647 am CDT Thursday Oct 2 2014

/12z taf/

Concerns...some MVFR ceilings this morning. A cold front will bring a
wind shift and thunderstorms to the taf airports this afternoon.

Some stratus across the region this morning is causing brief
bkn014-018 ceilings but the stratus should stay mostly few-scattered this
morning at the taf sites. However...middle level accus is causing
scattered-broken skies around 120 kft. South winds will turn to the
southwest and increase to 14-20 kts by midday. A front will move
into the region this afternoon with thunderstorms developing along
the front. The best timing for thunderstorms in the metroplex is
between 21/22z - 23/00z from west to East. Waco is likely to
experience thunderstorms from 22-00z. The storms could be severe
producing hail and/or damaging winds.

VFR conditions and clearing skies will occur behind the front.
The winds overnight will be from the northwest between 5-15 kts.
The winds will become more northerly on Friday and increase around
midday as another surface high moves into the region.



Previous discussion... /issued 331 am CDT Thursday Oct 2 2014/
water vapor loop shows a pronounced shortwave trough over New Mexico
rapidly moving eastward toward the region. Forcing for ascent ahead
of this feature is already reaching the aircraft data
indicates lifting and dynamic cooling of the middle level temperature
profile. Where enough moisture exists aloft...across the northwest zones
and Oklahoma...this lift is allowing elevated parcels to reach their
level of free convection and convect. This scattered elevated convection will remain
primarily north of the region this morning...but the northwest and
northern zones will have a chance of morning showers or storms.

The cold front is now entering the Texas Panhandle and is forecast
to reach the northwest zones by midday. Model guidance is an hour or two
faster with the front...but overall there is little change to the
forecast thinking of the last few days. Ahead of the front...south
to southwest winds of 10 to 20 miles per hour will ensure a warm morning and
once the low stratus scatters out by midday...sunshine will boost
temperatures into the low to middle 90s over the region. These hot temperatures and
dewpoints near 70 occurring in conjunction with dynamic cooling
aloft will result in a moderately unstable airmass developing this
afternoon with cape reaching 2000-2500 j/kg. While a fairly strong
inversion near 850mb will cap off convective potential early in the
day...the combination of dynamic lift ahead of the shortwave
trough...convergence along the front...and afternoon heating will
all work to erode convective inhibition over the area.

Surface based convection is expected to form along the front over
the northwest zones around 1 PM as the cap begins to break. Convection will
continue to develop southward along the front through the middle-late
afternoon hours as it marches southeast into the central zones. We
expect frontal passage around 3 PM near Gainesville...5 PM near dfw...and 7pm
near Waco. When the front crosses the I-35 corridor a squall line
will begin to take shape...which means there may still be a few gaps
in the line at this time. A fully developed and mature squall line
will exist as the front moves east of the I-35 corridor early this
evening...and it appears the threat for damaging winds is highest in
this region. The cap will be a little stronger over the western and
southwestern zones...and activity will likely be more isolated
there. Where convection is more isolated...supercellular storm Mode
is favored...which means there is an enhanced large hail threat in
addition to a wind threat. While low level wind profiles do not
appear favorable for low level rotation...surface based supercells
can still produce isolated tornadoes given the right mesoscale
conditions...but this cannot be forecast reliably at this time range.

The front and line of storms will rapidly clear the region from
northwest to southeast this evening. Drier and slightly cooler air
will move into the region overnight...but northerly winds will not
really increase until Friday when a stronger high pressure surge
arrives. Highs Friday will be cooler and generally top out near 80
in the north and the middle 80s south. The surface high will settle in
right over the County Warning Area by sunrise Saturday and winds will go calm. With
dewpoints by this time in the 30s and 40s...lows Saturday morning
should reach the 40s for a large portion of the County Warning Area...with low 50s
for the dfw area and the southeast County Warning Area. Saturday will be sunny and
pleasant with highs topping out near 80...but winds will switch to
the south by Saturday evening.

Increasing moisture and a moderation of temperatures back above normal will
occur Sunday into early next week. The 00z European model (ecmwf) has an outlier
solution of a strong shortwave rotating through in northwest flow
aloft on Monday which brings another weak front and a chance of rain
to the area. The GFS/Canadian/UKMET are much weaker with this energy
and therefore show dry weather with high temperatures warming into the 90s
with lows in the 60s and 70s. Will keep forecast the dry but as a
nod to the European model (ecmwf) potential will nudge high temperatures downward into the
middle to upper 80s for next week instead of the climatologically bold
forecast of lower 90s.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 93 59 82 50 80 / 70 20 0 0 0
Waco, Texas 95 58 84 49 81 / 50 40 5 0 0
Paris, Texas 91 57 78 45 76 / 80 60 0 0 0
Denton, Texas 92 54 81 43 80 / 60 10 0 0 0
McKinney, Texas 92 56 81 43 78 / 80 30 0 0 0
Dallas, Texas 93 60 82 51 80 / 70 30 0 0 0
Terrell, Texas 94 59 82 48 79 / 70 50 0 0 0
Corsicana, Texas 94 61 83 49 79 / 60 60 5 0 0
Temple, Texas 95 60 85 50 81 / 30 50 5 0 0
Mineral Wells, Texas 92 54 82 44 81 / 30 10 0 0 0


Forward watches/warnings/advisories...




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