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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
1221 PM CST Sat Jan 31 2015

Aviation...
/18z tafs/

Concerns...deteriorating cigs/vsby...thunder potential.

Metroplex...
showers will increase in areal coverage this afternoon...with
prevailing rain and MVFR ceilings by sunset. IFR ceilings will
settle in this evening and persist during morning flights Sunday.
Expected any isolated thunder will be confined to central and East
Texas...generally southeast of metroplex taf sites...and during
the nighttime lull in commercial flights. Winds will begin veering
middle-morning Sunday in advance of a cold front...rapidly improving
conditions.

Extended portion of dfw taf (sunday afternoon)...
although metroplex airports will already be in north flow by
midday Sunday...the strongest northwest winds will lag behind the
initial wind shift. Middle to late afternoon...prevailing speeds may
top 20kts...with occasional gusts in excess of 30kts. Expect
runways will be whisked dry by that time...but dfw diagonals will
still be favored to minimize the crosswind component.

Waco...
MVFR ceilings have already arrived...and conditions will only
deteriorate further as the low-levels saturate. Precipitation Mode
will be primarily showers...but isolated thunderstorms will be
possible this evening through Sunday morning. If thunder does
occur at the Waco terminal...it is most likely to happen when the
tower is closed and there are no commercial flights. IFR ceilings/visibility
will prevail during morning arrivals/departures...but veering
winds in advance of the cold front will quickly improve conditions
middle to late morning Sunday.

25

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Previous discussion... /issued 258 am CST Sat Jan 31 2015/
as I write this an area of virga sits over western counties
moving northeast at 25 miles per hour. An occasional rain drop may make it
to the surface...but the 00z sounding showed very dry air between
750 and 950 mb. It will take a bit of precipitation to moisten this
layer. As a result...although precipitation onset timing has changed
little...I have decreased quantitative precipitation forecast since a good portion of our
expected rain will evaporate as it moistens this layer. Many
areas will now struggle to get a quarter inch out of this
system...with a bit more than a third of an inch possible in the
northwest and northern counties.

The precipitation should also shut off faster Sunday as the accompanying
cold front dries out the lower levels. Better precipitation chances are
now confined to the southeastern half of north/central Texas after
noon.

The upper low prognosticated to sweep east across coastal Texas Tuesday
night into Wednesday has its track shifted a bit farther
north...and low probability of precipitation have been adjusted a bit north as well. I
would not be surprised to see the track shift back south again
tomorrow...that seems to be the pattern with this system. At any
rate...with the trough passage another cold front will sweep
south across the area. GFS and European model (ecmwf) generate quantitative precipitation forecast behind this
front...but moisture is limited to below the inversion and this
would appear to be drizzle rather than showers or rain.

Temperatures will remain seasonably cool...with Wednesday likely the
warmest day of the week with highs in the upper 50s/low 60s. 84





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Preliminary point temps/pops...
Dallas-ft. Worth, Texas 55 48 57 29 44 / 60 90 60 10 5
Waco, Texas 55 51 61 32 47 / 60 80 70 10 5
Paris, Texas 54 44 55 27 42 / 40 90 70 10 5
Denton, Texas 53 45 54 28 44 / 70 90 60 10 5
McKinney, Texas 55 46 56 28 43 / 60 90 70 10 5
Dallas, Texas 55 48 58 30 44 / 60 90 60 10 5
Terrell, Texas 56 49 59 30 44 / 50 90 70 10 5
Corsicana, Texas 56 51 61 31 45 / 50 80 70 10 5
Temple, Texas 56 52 63 33 48 / 60 70 70 10 5
Mineral Wells, Texas 52 46 53 28 46 / 90 80 40 10 5

&&

Forward watches/warnings/advisories...
none.

&&

$$

25/05

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