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Area forecast discussion 
National Weather Service Fort Worth Texas
613 PM CDT Tue Oct 25 2016

a shortwave trough currently making its way across the central
part of the Continental U.S. Is generating convection in parts of the
northern and Central Plains. A persistent upper ridge over Texas
will keep convection to a minimum across our forecast area.
However, we will need to keep an eye on trends immediately
northeast of the Dallas-Fort Worth area approximately 24 hours
from now, when a weak front makes its way into northeast Texas.
This feature could become the focus of a few showers and storms
which may affect northeast cornerposts by this time tomorrow.
Otherwise, mid and high level clouds seem to be the only result
for the time being.

Low clouds will likely develop over The Hill Country tonight and
advect northward within the 20kt winds at 925 mb. Kact may deal
with a few hours of IFR cigs, but at this time it appears that any
cigs which occur in the metroplex will be in the MVFR range. VFR
will return to all areas by 18z Wednesday.



Previous discussion... /issued 420 PM CDT Tue Oct 25 2016/

The main concerns for this forecast package revolve around
fog/stratus potential during the overnight hours. In addition,
rain chances return to the forecast for parts of North Texas late
Wednesday into Thursday. Thereafter, mostly dry conditions are
expected with a low chance for thunderstorms early next week.
Otherwise, above normal temperatures are forecast through the
entire outlook.

Satellite imagery at this hour revealed that a large veil of
cirrus remained in place across a majority of north and central
Texas. This cirrus shield is associated with a low amplitude trough
that continues to slide eastward through the central portion of
the U.S. In its wake, drier air aloft should result in partial
clearing after midnight.

For tonight---as clearing occurs, low level moisture will be
drawn northward ahead of an approaching cold front currently
sliding southward through portions of Kansas and Nebraska. With
clearing skies and generally light winds, there's a high enough
potential to include patchy fog into the forecast. Forecast
soundings suggest that this potential will be maximized across an
area characterized by 1-2 degree dewpoint depressions and the most
likely area for fog to occur will be along and south of a Comanche
to Hillsboro to Palestine line. There may be some potential for
patchy dense fog, but i'll let the evening shift have a closer
look at this possibility. If boundary layer flow is a little
stronger than currently advertised, the aformentioned area may
only experience periods of very low stratus in the morning. The
increase in low level moisture should result in mild overnight

For Wednesday and Thursday---a majority of Wednesday appears to be
dry, though I cannot rule out the potential for some weak convection
along the Red River during the late morning and early afternoon
hours. The better threat for convection appears to be during the
afternoon and evening hours on Wednesday. I've introduced some
chance and slight chance pops along the Red River and across
northern/northeastern zones. Synoptic models show a shortwave
trough diving southward through The Ark- la-tex which when
combined with the cold front should provide sufficient lift for
convection. In addition, most hi- resolution model guidance
continues to indicate the chance for showers and a few
thunderstorms, adding a bit more confidence to introduce some low
pops into the forecast. In general, the overall severe weather
threat appears low due to marginal amounts of shear and
instability. I won't rule out a small risk for some small hail and
gusty winds, however. The cold front should lose a majority of its
baroclinicity before lifting northward on Thursday.

For Friday through Monday---the forecast appears dry as the 500 mb
ridge centers itself across the Big Country. Low level moisture
will stream northward and with continued subsidence, temperatures
should warm above normal values. The GFS does push a front south
towards the Red River on Saturday, but the European model (ecmwf) keeps this
boundary further to the north. Given how far displaced to the
north the upper air trough is in both model solutions, i'll side
with the European model (ecmwf) output which keeps the front across northern

For Tuesday and beyond---a low chance for rain will return to the
forecast on Tuesday as models advertise good moisture advection
towards the north. Right now, it appears that this convection will
be isolated to widely scattered and i'll only include a 20 pop for
southern/southeastern zones at this time. Convection will likely
be diurnally driven, given that a majority of the favorable
dynamics for widespread lift will be located to the north of the



Preliminary point temps/pops...
Dallas-ft. Worth 65 84 64 85 63 / 5 10 20 5 5
Waco 61 85 61 86 61 / 5 10 10 5 5
Paris 58 81 60 84 61 / 5 20 30 5 5
Denton 62 84 61 84 60 / 5 10 20 5 5
McKinney 63 82 62 84 62 / 5 10 20 5 5
Dallas 65 84 64 85 64 / 5 10 20 5 5
Terrell 62 83 63 84 60 / 5 10 20 5 5
Corsicana 62 84 62 85 61 / 5 10 20 5 5
Temple 61 84 61 86 60 / 5 10 10 5 5
Mineral Wells 62 85 61 86 60 / 5 10 20 5 5


Forward watches/warnings/advisories...



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