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Area forecast discussion 
National Weather Service Fort Worth Texas
1239 PM CDT Thursday Apr 17 2014

MVFR ceilings will prevail through the day and into tonight. Low level
flow is weak and there is a nearly saturated layer between
800-900mb that is precipitating very light drizzle. Visibility may drop
to 4sm in heavier areas of drizzle/mist this afternoon. Ceilings are
lowest over the western metroplex where they have fallen below
2000ft...but it appears near surface dry layer is thicker over
eastern sites with kdal still VFR. IFR ceilings look like they will
remain just west of all taf sites through the period. Hard to say
whether ceilings will drop below 2000ft this evening...but for now
confidence is low and have kept metroplex sites generally above
this level tonight on the presumption that low level flow will
become northeasterly and reinforce near surface dry layer. All
MVFR ceilings should clear out tomorrow morning.

For Waco...have MVFR ceilings arriving in the next hour or so as
moisture moves in from the west. MVFR ceilings will prevail into
tomorrow morning. Again with flow so weak...amendments to exact
ceiling heights may be required later.


satellite imagery and upper air analysis shows a disturbance
moving into the Texas Panhandle at this hour. Low clouds continue
to spread north ahead of this disturbance and drizzle/light rain is
being reported underneath these low clouds at several sites across
the southern half of the County Warning Area. Light returns on area radars show
the light rain/drizzle moving north towards the I-20 corridor. Weak
lift combined with increasing moisture will allow scattered
showers to develop across the region today. This afternoon...the
concentration of rain may become more focused near a cold front
moving towards our northwestern counties. Increased probability of precipitation for the
remainder of the day to 30 percent across the region with 40 probability of precipitation
in the northwest quadrant this afternoon. Forecast soundings
continue to show a well capped environment through the day and
kept thunder out of the forecast.

Otherwise...expect overcast to mostly cloudy skies for most of the
day. Lowered daytime highs a few degrees due to the cloud cover.



Previous discussion... /issued 400 am CDT Thursday Apr 17 2014/
early morning surface analysis indicated a low pressure system
across southeast Minnesota with a cold front trailing southward
into the Southern Plains across north central Oklahoma and into
the Texas Panhandle. This front will sag southward a little
farther through the day but is not expected to move through North
Texas. Across our part of the state...southerly flow has helped
transport low level moisture northward...resulting in increasing
cloud cover and warmer temperatures. Some scattered convection
developed over central Texas over the last couple of hours which
is a bit surprising given the expected thermodynamic profile
across the region. 00z sounding data and 7z model analysis
indicate a strongly capped environment with moisture confined
generally below 800mb. The model analysis clearly appears to be in
error as the atmosphere would have to be modified significantly to
get convection. Water vapor imagery does show a fairly strong
shortwave moving through West Texas...ahead of the main
disturbance which is a little farther west. Capping inversion is
likely much weaker across central least immediately
downstream of the approaching shortwave...where lift is sufficient
to overcome any remaining inhibition. Despite the poor model
performance downstream of this lead shortwave...think the
convection should be confined well south of our area through the
morning and will likely weaken as it progresses farther east.

Across our area today...cloudy skies will prevail with
temperatures in the upper 60s. Lift from the main disturbance will
increase later today...but strong capping is expected to remain in
place with any precipitation expected to be light showers beneath
the cap. Best chances will be this afternoon across the northwest
counties closer to the surface boundary and better lift to the
north. This system moves east by tonight but leaves behind ample
low level moisture.

Friday and Saturday should be dry with temperatures warming into
the upper 70s and lower 80s beneath ridging aloft. By Saturday
night another disturbance moves out of the southwest U.S. And
spreads ascent across North Texas. Convection should develop
initially across West Texas late Saturday night and move east with
time. Best chances for showers and thunderstorms across North
Texas appears to be during the day Sunday when lift from the upper
trough is strongest. Ample heating Sunday afternoon will lead to
surface based cape in excess of 1500j/kg across much of the area.
Wind fields are generally weak although deep layer shear will
increase with the approach of the upper trough Sunday afternoon.
There will be the potential for some strong to marginally severe
storms Sunday afternoon. Upper trough will continue to provide at
least some lift across North Texas Sunday night into early Monday
when a weak front approaches the area. Raised probability of precipitation Sunday night
and added some low probability of precipitation across the area for early Monday.

Beyond looks dry at least through midweek under riding
aloft with more active weather toward the end of next week.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 66 57 77 61 79 / 30 20 10 10 10
Waco, Texas 68 54 76 55 79 / 30 20 10 10 10
Paris, Texas 66 50 75 55 77 / 30 20 10 10 10
Denton, Texas 66 53 75 56 78 / 40 20 10 10 10
McKinney, Texas 66 52 75 56 78 / 30 20 10 10 10
Dallas, Texas 66 57 77 61 80 / 30 20 10 10 10
Terrell, Texas 68 53 75 58 78 / 30 20 10 10 10
Corsicana, Texas 66 54 77 59 79 / 30 20 10 10 10
Temple, Texas 68 55 77 57 79 / 30 20 10 10 10
Mineral Wells, Texas 68 58 74 57 79 / 40 20 10 10 10


Forward watches/warnings/advisories...