Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Fort Worth Texas
235 am CST Friday Nov 28 2014
the upper level pattern across noam will change little over the
next seven days as a deep wintertime upper level low remains
intact over northern Hudson Bay. Farther south across our section
of the country...an upper level ridge over the western U.S. Will
flatten during the next 48 horus with near zonal flow prevailing
afterward. Within this zonal flow...a weak short wave trough will
move across the region late Sunday/early Monday as a cold front
arrives. This front may produce isolated to scattered light
showers east of the I-35 corridor on Monday...but any rainfall
will be light. Have maintained a slight chance of warm advection
showers on Thursday.
Today through Saturday...a strong surface pressure gradient will
result in strong and gusty southerly winds and warming
temperatures through the period. Some gusts up to 35 miles per hour are
possible. Currently...do not think a Wind Advisory will be
needed...but one may be required on Saturday afternoon. With lower
dewpoints presiding over the northwestern counties on
Saturday...the wind and above normal temperatures will result in
an elevated fire weather concern during the afternoon hours.
Sunday will be a slightly warmer than Saturday...but the southerly
winds will not be as strong as the pressure gradient relaxes a
little ahead of a nearing cold front. The cold front should be
able to enter the northwestern counties shortly after midnight and
roughly to a Paris to dfw and Goldthwaite line before daybreak
As the cold front pushes through the rest of the forecast area on
Monday morning...there will be a slight chance of light showers
during the day. Otherwise...it will be noticeably cooler Monday
and Tuesday as a Canadian air mass spreads over North Texas.
Temperatures will below normal on Tuesday with morning lows in the
upper 20s over the northwest counties to the middle 40s over the
southeast. Highs Tuesday will be mostly in the low to middle 50s.
As the Canadian air mass slides east of the region on
Wednesday...a return of southerly winds will allow temperatures
to rebound back to around normal for both Wednesday and Thursday.
Day 7-10 outlook...another strong cold front is being indicated
on either Saturday /Dec 6 per GFS/ or late Sunday /Dec 7 per
European model (ecmwf). Both solutions are producing rainfall along and behind the
front with the GFS being more aggressive with a widespread
moderate to heavy rainfall event Saturday through Sunday. 75
/issued 1140 PM CST Thursday Nov 27 2014/
Concerns...low-level wind shear tonight...gusty winds Friday.
A surface high has moved into the southeast states. Southerly
surface winds have returned but are quite light. However...above
the shallow nocturnal boundary layer...a low level jet of 35kts has ensued
and will continue throughout the night. With near-calm winds at
the surface...have introduced low level wind shear into the metroplex tafs.
These strong winds will mix to the surface by middle-morning Friday.
GFS/NAM MOS are now generating sustained 20kts by 21z (3 PM cst).
With deepening Lee troughing...it stands to reason that this
momentum will sustain itself throughout the day Friday.
The surface layer will remain well mixed Friday night...with wind
speeds diminishing very little. The gusty south winds will
continue to steadily increase low-level moisture. Stratus may
invade central Texas Saturday morning...but this is currently
beyond the Waco taf. 25
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 68 53 76 62 79 / 0 0 5 5 10
Waco, Texas 68 54 76 61 78 / 0 5 5 10 10
Paris, Texas 63 52 73 61 76 / 0 0 5 10 10
Denton, Texas 67 51 74 59 78 / 0 0 5 5 10
McKinney, Texas 65 54 74 61 76 / 0 0 5 5 10
Dallas, Texas 67 53 75 62 78 / 0 0 5 5 10
Terrell, Texas 66 54 74 61 76 / 0 0 5 10 10
Corsicana, Texas 66 55 77 62 77 / 0 5 5 10 10
Temple, Texas 69 54 76 62 77 / 0 5 5 10 10
Mineral Wells, Texas 70 48 76 55 77 / 0 0 5 5 5