Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Fort Worth Texas
941 PM CDT Sat Mar 15 2014
convection continues to decrease in intensity and have cancelled
the remaining counties in the Severe Thunderstorm Watch. Showers
and storms will continue to push east across the eastern zones and
will have the highest probability of precipitation there. Will continue with low probability of precipitation for
the rest of the County Warning Area for any additional activity in clsoer
proximity to the upper low.
Winds behind the cold front tomorrow will be sustained between 20
and 30 miles per hour with gusts up to 40 miles per hour and issued a Wind Advisory
between 12z and 00z to accont for the high winds.
Dfw airports...we continue tracking a line of showers and storms through
the dfw metropolitan currently. Current speed estimates indicate main
line should be east of the airports by 01z or 8 PM...then vcsh and
MVFR ceilings ahead of the cold front and with the upper level system
passing across the region. Some brief periods of VFR are certainly
possible as well. Post convective winds will likely be gusty out
of the west 15-30 kts...before prevailing from northwest under 10 kts.
After the frontal passage around midnight...will see gusty northwest winds around
15 kts...becoming sustained 20-25 kts with gusts in excess of 35
kts at times. Ceilings will rise with the frontal inversion to 025
after sunrise Sunday...going into low VFR between 030-040 for much
of the day Sunday. For now...have left any -ra out of the extended
part of the taf.
Waco...similar trends to dfw with tracking convection off to the
northwest. Will have a 2 hours thunderstorms in the vicinity period middle-late evening with
some uncertainties on how much coverage gets into the central
Texas area. Otherwise...current satellite trends dictate a more
positive ceiling forecast in VFR before frontal passage after midnight.
After frontal passage...will hold to MVFR ceilings though some guidances and
soundings are showing IFR possible by morning. Have a hard time
with that considering the frontal inversion will be slowly
deepening with time. Otherwise...south flow around 10 kts will
shift west-southwest by late evening...then go northwest 10-15 kts after midnight.
Strong cold air advection will drive gusty northwest winds 20-25 kts with gusts to 35
kts by middle morning and after...as ceilings rise into low VFR 030-040
by midday and after Sunday.
line of strong to severe storms continues to push east and
southeast across North Texas. Have cleared most of the watch...as
activity nears the eastern extent of Severe Thunderstorm Watch 29.
Added Coryell..McLennan and Hopkins County as severe storms will
near these counties shortly. After coordination with Storm Prediction Center...will
not add anymore downstream counties...as intensity trends are
expected to be going down with the loss of heating. Also updated
probability of precipitation to account for ongoing radar trends.
Previous discussion... /issued 257 PM CDT Sat Mar 15 2014/
a well defined short wave will open up and lift northeast across
Oklahoma tonight while a secondary piece of energy drops south
into far West Texas/northern Mexico. Large scale lift coupled with
abundant moisture and moderate instability will result in numerous
showers and thunderstorms. Although afternoon cloud cover has
limited low level destabilization...the middle levels of the
atmosphere remain unstable and there is enough vertical wind shear
to sustain some updrafts. Therefore...some storms may briefly
become severe with large hail and damaging winds. Although surface
winds are backed at many locations currently...the wind fields are
largely unidirectional above the surface. Therefore...the tornado
threat is fairly low...but not zero.
Rain and thunderstorm chances will decrease from west to east
through the evening as dry air filters in on the back side of the
exiting short wave. Once the trough axis passes to the east...a
cold front will move quickly southeast across North Texas.
Although the cold front will provide some low level forcing...large
scale subsidence should keep precipitation light overnight.
Sunday will be a cloudy...cool and windy day with near steady or
slowly falling temperatures. A north to northwest wind will
increase between 20 and 30 miles per hour with some gusts to 40
miles per hour...especially across the western two thirds of the region.
Therefore...a Wind Advisory will most likely be needed for a
large portion of the area. Since relative humidity values will
remain high and the ground will be moist from today/S
rainfall...fire weather concerns will be minimal.
Earlier model runs were showing a potential for some winter
precipitation across the western/southwestern zones near the core
of the upper low Sunday afternoon and Sunday night. However...the
current model solutions...including the 12z European model (ecmwf)...keep the
upper low well west and south of the County Warning Area. Therefore...we will not
mention any winter precipitation across North Texas with this
Clouds will clear Sunday night and wind speeds will decrease which
will lead to optimal radiational cooling. Locations generally
north of the Interstate 20 corridor will have a potential to fall
below freezing for a few hours overnight Sunday/early Monday
Temperatures Monday will warm steadily under abundant sun.
However...a warm air advection pattern will not begin to take
shape until Monday night/Tuesday when a surface trough deepens
across the northern and Central Plains in response to a developing
upper trough across the central rockies. Tuesday should be a warm
and breezy day with afternoon highs from the lower 70s to the
A weak cold front will move into the region Tuesday night/
Wednesday but will only bring slightly cooler and drier air. The
drier air will only be temporary as surface high pressure builds
quickly east and another surface trough deepens across the High
Plains. This pattern will bring a return of Gulf moisture and
warmer temperatures Thursday through Friday.
A progressive short wave trough is prognosticated to rotate through the
northern branch of the jet stream on the weekend. The passage of
the trough axis across the Central Plains will send a weak cold
front southward into North Texas. Lift along the cold front should
be enough to produce scattered showers and thunderstorms on
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 51 51 33 62 46 / 30 30 10 5 0
Waco, Texas 49 54 34 65 44 / 50 30 20 5 0
Paris, Texas 52 55 32 57 39 / 90 30 10 10 5
Denton, Texas 48 48 31 61 43 / 30 30 10 5 0
McKinney, Texas 48 50 30 58 39 / 50 30 10 5 0
Dallas, Texas 50 52 33 62 44 / 40 30 10 5 0
Terrell, Texas 50 56 33 59 43 / 80 30 10 5 0
Corsicana, Texas 53 58 34 62 44 / 90 30 10 5 0
Temple, Texas 48 54 35 65 42 / 30 30 20 5 0
Mineral Wells, Texas 45 49 31 67 40 / 30 30 10 0 0
Wind Advisory from 7 am to 7 PM CDT Sunday for txz091>095-