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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
1146 PM CDT Monday Mar 30 2015

Aviation...
no major changes in thinking from the 00z taf package. Skies will
remain VFR for the first few hours of the taf valid time with
mainly thin...high clouds. A 40 knot low level jet...as indicated
on the kfws VAD wind profile...will bring a return of low clouds
to Waco between 07 and 08z and the metroplex taf sites between 09
and 10z. Overall...prevailing ceilings should not fall below 1000
feet...but Waco may temporarily fall to 800 feet around sunrise
Tuesday morning. All low clouds will lift and scatter late morning
Tuesday with vigorous boundary layer mixing. VFR conditions will
prevail Tuesday afternoon and evening...then MVFR ceilings will
return overnight Tuesday/Wednesday morning.

An approaching upper level trough will bring increasing large
scale lift to North Texas late Tuesday afternoon and evening as
well as help destabilize the middle levels of the atmosphere. A few
storms will develop late Tuesday afternoon and evening but these
should remain well west of the Interstate 35 corridor. After
06z...storms will increase in coverage slightly as the upper
trough moves into West Texas. For now we will leave the mention of
storms out of the extended portion of the dfw taf since storm
coverage should be limited through 12z. Slightly better storm
coverage is expected after 12z Wednesday once the upper trough
gets closer to the region.

A south wind will prevail between 8 and 12 knots tonight and
between 12 and 17 knots Tuesday.

79

&&




Previous discussion... /issued 353 PM CDT Monday Mar 30 2015/

The weather pattern across the region for the next week remains
progressive and active with several chances for rain/storms...but
unfortunately the chance for significant rainfall does not appear
favorable. Warm weather is expected to persist through Friday and
then a cold front will lower temperatures for a few days.

Mostly cloudy skies have prevailed across a good part of the
region today due to a combination of high and low clouds.
Temperatures this afternoon vary from the low 70s in the east
where the low clouds have hung in longer...to the low 80s in the
west where thin high clouds have been located. A shortwave is
moving across the Texas Panhandle with weak middle and upper level
ridging over the north and central Texas areas. Some elevated
returns may appear on regional radars late this afternoon and
evening but most precipitation...if not all...is expected to
evaporate before reaching the ground due to dry air in the middle and
lower levels of the atmosphere. A warmer night is expected tonight
with lows mostly in the lower 60s...but a few locations may dip
into the upper 50s around daybreak.

An upper level low currently located west of Baja California California will
move into Mexico Tuesday and then across the region Tuesday night
and Wednesday. Many of the models are producing quantitative precipitation forecast across the
region on Tuesday but a decent cap favors a dry forecast for most
of the area tomorrow. However...a dryline will be located west of
the area tomorrow afternoon as large scale lift begins to spread
east across the state in advance of the upper level disturbance.
Temperatures near the dryline and across our western zones will
warm into the 80s which may be enough to weaken the cap and allow
a few storms to develop. In our western counties...forecast
soundings keep the cap in place during the afternoon but do weaken
the cap around sunset. If a storm or two develops on the
dryline...they could move into our western counties during the
late afternoon or early evening hours. Have adjusted probability of precipitation for
tomorrow afternoon to only 20 percent in the west and Northwest.
Cape and shear values support a threat for strong or possibly
severe storms with a main threat for large hail.

Rain and thunderstorm chances will spread across the region
Tuesday night and Wednesday. The best rain chances will be over
the eastern half of the County Warning Area Wednesday afternoon where the moisture
depth is greatest. Additional isolated strong or severe
storms are possible across the region during the day on
Wednesday. The rainfall is not expected to be widespread and
amounts are not expected to be more than a quarter of an inch on
average. Some areas will see more than a quarter of an inch of
rainfall under a strong or severe storm but others will not
receive any rainfall at all. As the shortwave moves east of the
region Wednesday evening...the rain chances will end.

A few thunderstorms are also possible on Thursday with a decent
threat for severe weather if the storms develop. The dryline is
expected to surge to a location east of Interstate 35/35w Thursday
afternoon while temperatures warm into the upper 80s and lower
90s. Cape values along and ahead of the dryline are forecast to be
over 2000-3000 j/kg with cin values weakening to breakable levels
in the middle to late afternoon hours. Shear values are decent too
but the missing piece for storms may be a decent forcing
mechanism. The latest model runs do not indicate strong surface
convergence along the dryline but some of the models are
indicating a weak disturbance possibly moving over the dryline in
the afternoon hours. Any weak disturbance could provide enough
lift to break the cap and allow storms to develop. This situation
needs further watching and analysis as there could be severe
storms along the dryline on Thursday. For now...will keep a 10 pop
for the afternoon hours as none of the models are resolving storm
initiation and the potential for storm development may be
isolated.

On Friday...a cold front will slide across the region with
additional rain and thunderstorm chances along the front. The
latest European model (ecmwf) is about 6 hours faster with the timing of the front
and significantly drier over the GFS. Due to the differences in
the models...will keep probability of precipitation on the lower end at 20-30 percent.
Saturday is expected to be dry but rain chances return Saturday
night through Monday. The upper level flow will transition back to
southwest flow aloft as another upper level trough develops over
the West Coast. The models quickly return moisture back to the
region but the moisture return may be too aggressive and too quick
in the wake of the cold front. Better rain chances are likely
Sunday night into Monday.

Jldunn




&&



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 64 81 64 75 66 / 10 10 20 30 10
Waco, Texas 62 80 64 77 65 / 10 10 20 30 10
Paris, Texas 60 75 61 73 62 / 10 10 20 40 20
Denton, Texas 63 80 63 75 65 / 10 10 20 30 10
McKinney, Texas 62 79 62 73 65 / 10 10 20 40 10
Dallas, Texas 64 80 64 74 66 / 10 10 20 30 10
Terrell, Texas 61 78 62 73 63 / 10 10 20 40 20
Corsicana, Texas 62 78 63 76 64 / 10 10 20 40 20
Temple, Texas 62 80 64 78 63 / 10 10 20 30 10
Mineral Wells, Texas 60 83 63 78 64 / 10 20 30 30 10

&&

Forward watches/warnings/advisories...
none.

&&

$$

79/25

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