Area forecast discussion...updated
National Weather Service Fort Worth Texas
642 am CDT Thursday may 23 2013
Aviation...
IFR ceilings have developed at all taf sites this morning as rich
Gulf moisture has spread back into the area. Expect the ceilings
to persist until around 15z /10 am CDT/ before the stratus lifts
and scatters out. Some patchy fog also expected at all taf sites...
but visibility restrictions down to 4-5sm are not expected to be
persistent.
Scattered cumuli are expected this afternoon as strong may sun
promotes mixing with cloud bases rising to over 3000 feet. A repeat
of the low clouds is forecast at all sites tonight/Friday
morning...but the ceilings are forecast to remain in MVFR
category with bkn012-bkn018 forecast after 10z /5am CDT/ Friday.
Chances for thunderstorms near the North Texas taf sites today
will be limited. The mesoscale convective system in central and
southern Oklahoma should spread southeast into the kprx area later
this morning...but those impacts will remain northeast of dfw
metropolitan airports. Later this afternoon and tonight...a cluster of
strong to severe thunderstorms is forecast to develop in West
Texas and spread east and southeast near a stationary front. Most
of this activity is expected to remain west of the taf sites...but
later forecasts will closely monitor the convective potential in
case the initial development occurs farther east than forecast. 09
&&
Previous discussion... /issued 312 am CDT Thursday may 23 2013/
warm advection within the low level southeast flow is increasing dew
points throughout most of Texas this morning...and low level
moisture will remain in place for the next several days. A weak
warm front is located this morning near the Red River and convection is
starting to form in southern OK. Northwest flow aloft should advect the
storms over northeastern counties this morning.
Precipitation forecast over the next few days is quite difficult due
to model differences in handling the weak forcing and determining
the locations where storms will occur. The weak ridging over Texas
is not strong enough to produce a subsidence inversion to cap off
convection and model pop solutions for our area range from dry to
storms across much of North Texas. This uncertainty will last through
the weekend. Should models begin to converge on a solution...the
low probability of precipitation currently forecast will need to be raised for the areas
where the precipitation becomes more likely.
There is some consensus among the guidance which suggests that
convection will break out near the dry line in West Texas this
afternoon...with some sort of mesoscale convective system moving south and spreading east
Thursday evening into the overnight hours. Confidence is higher
in the southward moving mesoscale convective system than the convection spreading
east...so I have slight chance probability of precipitation in the forecast. The
convection may initially affect northwest counties...expanding
overnight to affect much of the northern half of the North Texas
area on Friday.
The process may repeat itself Friday evening...with low probability of precipitation
lingering in the northern half Saturday and across northern
counties through Sunday morning...highly dependent on where
convection does form and evolve into an mesoscale convective system...and what direction
it moves.
With south flow continuing through the week...temperatures will
remain seasonable with afternoon highs in the 80s/90s and morning
lows in the upper 60s/70s. Afternoon highs are highly dependent
on where and to what extent convection occurs.
In the extended...the European model (ecmwf) and GFS suggest that an upper trough
will move into the Great Basin by Thursday...extending south to
northern Mexico. This system has the potential to produce
convection next Thursday and Friday...and I added low probability of precipitation to the
grids for those two days. 84
&&
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 88 72 86 71 85 / 10 20 20 10 20
Waco, Texas 90 73 88 69 87 / 10 10 10 10 10
Paris, Texas 85 68 81 69 82 / 40 20 20 10 20
Denton, Texas 87 70 84 70 83 / 10 20 20 10 20
McKinney, Texas 88 70 85 70 84 / 10 20 20 10 20
Dallas, Texas 90 73 88 72 87 / 10 20 20 10 20
Terrell, Texas 89 71 87 70 87 / 10 20 20 10 20
Corsicana, Texas 90 71 89 70 87 / 10 10 10 10 10
Temple, Texas 90 72 87 69 86 / 10 10 10 10 10
Mineral Wells, Texas 91 71 86 70 84 / 10 20 20 20 20
&&
Forward watches/warnings/advisories...
none.
&&
$$
