Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Fort Worth Texas
1129 am CST Friday Mar 7 2014
concerns...winds today...IFR-MVFR ceilings late tonight/Saturday morning
and frontal passage on Saturday.
A surface low over the Texas Panhandle will continue to sink
southward across West Texas during this forecast. A cold front
attached to the low will move through the metroplex and kact
16-18z on Saturday with northerly flow prevailing afterward.
Low level southerly flow today will be strong with gusts around
25 knots during the afternoon. Speeds will back off some tonight.
Winds will go northwest to north 15-20kts after frontal passage late
Saturday morning and continue through the afternoon. Speeds will
become 10-15kts Saturday evening.
VFR conditions with periods of high clouds are expected this
afternoon and evening. MVFR ceilings will advect over the taf sites
after 07z with kact going IFR 13-16z Saturday morning. The
metroplex sites may also go IFR...but a brief window of
opportunity and low confidence precludes adding to the 18z tafs.
On Saturday morning...expect ceilings to become MVFR after frontal passage
/17-18z/ and remain so through the afternoon and into the evening
the areas of fog that developed overnight had dissipated as of 10
am. High clouds are moving across the region at this
time...making skies mostly cloudy. Expect this band of high
clouds to move to the east of most of the forecast area by late
afternoon...so have adjusted the sky wording to partly sunny. A
feed of high clouds from the Pacific associated with the southern
branch of the jet stream will continue to move across central
Texas through this afternoon but partly sunny should suffice for
that too. The pressure gradient has increased across the forecast
area as a surface low over the eastern Oklahoma Panhandle sinked
southward. This has resulted in southerly winds increasing to 10
to 20 miles per hour across most of the north and central Texas. Have seen
some wind gusts to 40 miles per hour at Dyess AFB /kdys/ this morning. 58
Previous discussion... /issued 411 am CST Friday Mar 7 2014/
southerly winds have returned to North Texas and will continue to
increase in speed this afternoon as a surface low propagates
south into West Texas. This is in response to an approaching
upper trough currently moving into Utah. Afternoon humidity values
will drop below 30 percent across the western counties and with
the breezy southerly flow around 15-25 miles per hour...elevated fire weather
conditions are expected.
The cold front with this system will move through the County Warning Area
tomorrow. Current timing is into the northwest counties around 6am...the
metroplex by noon...Waco by 2 PM and through the rest of the County Warning Area
by 6 PM. Southwest flow at 850 will bring warmer air...ensuring a
Stout cap will be in place as the front moves through. This will
prevent convection from developing...but rain is still in the
forecast. Forecast soundings show decent moisture below the
cap which would allow for frontogentically forced showers along the
boundary as it moves through the County Warning Area. This would be most likely to
develop as the front nears the metroplex and continues south...once
the front reaches slightly better moisture. High-res WRF models
show this thin line of showers along the front quite well. Behind
the front...elevated showers will be possible in the afternoon as
large scale forcing approaches as the upper low nears the area.
The NAM soundings do show very little amounts of elevated
instability...but will continue to not mention thunder as primary
Mode will be elevated showers. Temperatures Saturday behind the
front will be in the 40s/50s with lows Sunday morning back in the
Models have been consistently cutting off a piece of the main
trough by Monday...but now are cutting it off further west...then
moving it into central Texas Monday evening. Moisture in the
atmosphere will likely be quite poor...with the GFS progging precipitable waters
less than 0.5 inches. Will continue to keep the forecast dry...but
any increase in moisture would lead to a need for probability of precipitation Monday and
Monday night. Southerly flow Monday will lead to a warm up with
highs in the upper 60s and lower 70s across much of the area.
Another large trough will drop into the western Continental U.S. Monday and
approach the plains on Tuesday. This front will send another
cold front south into North Texas Wednesday...but unfortunately...
moisture will remain limited and a dry forecast continues.
Northwest winds behind this front will be strong...with the European model (ecmwf)
progging 25 knots. These winds will bring in much cooler
temperatures...back into the 50s Wednesday afternoon with lows
Thursday in the 30s. Hampshire
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 69 48 55 35 57 / 0 5 50 20 5
Waco, Texas 67 50 58 34 55 / 0 5 50 40 10
Paris, Texas 65 42 58 35 54 / 0 5 50 40 10
Denton, Texas 70 48 54 31 56 / 5 5 40 20 5
McKinney, Texas 68 46 57 32 56 / 0 5 50 30 5
Dallas, Texas 69 48 58 36 56 / 0 5 50 30 5
Terrell, Texas 68 46 59 35 55 / 0 5 50 40 5
Corsicana, Texas 67 48 59 36 54 / 0 5 50 40 10
Temple, Texas 67 50 59 35 55 / 0 5 50 40 20
Mineral Wells, Texas 73 49 52 31 58 / 5 5 30 20 5