Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/04/18
Area Forecast Discussion...UPDATED
National Weather Service Shreveport LA
758 PM CDT Sat Nov 3 2018
.SHORT TERM...
Srly winds have dropped off a bit with the loss of heating/mixing,
but a 40-50kt SSW LLJ ahead of the deepening upper trough over
Wcntrl TX continues to result in low level moisture advection N
into the region, ahead of a cold front analyzed from near a ADM,
to GLE, to just E of MWL, to near a SEP line. Theta-e ridging
continues to expand NE along the LLJ axis, indicative of the cu
cigs that continue to expand NNE into Lower E TX/Wrn LA attm.
Already seeing a narrow line of convection that has developed
along the front early this evening, which has deepened in the last
hour given the strong large scale forcing ahead of the trough, and
steep H700-500 lapse rates along the trough axis over NW TX/Wrn
OK. This convection development is a little faster than the latest
HRRR but in agreement with the 18Z NAM/GFS, which suggests that
sct convection may develop ahead of this line over portions of NE
TX/SE OK/SW AR before the organized convection reaches McCurtain
County OK/portions of the I-30 corridor of NE TX prior to
midnight. Thus, have added chance pops early this evening for this
area before gradually expanding likely and categorical pops E
overnight. Have also raised pops a bit to likely/categorical
farther E across the Ern sections of Ncntrl LA, as the line should
reach this area by daybreak Sunday.
Not really convinced of the severe potential with the line, as the
steep lapse rates will mostly remain NNW of the I-30 corridor this
evening and weaken shortly after 06Z as the convection begins to
outrun the front into the more stable air farther E. However, an
isolated strong storm or two with small hail and locally gusty
winds still can`t be ruled out this evening before intensities
gradually diminish overnight. Did not make any changes to the
forecast min temps attm.
Have also allowed the Lake Wind Advisory to expire at 00Z as
scheduled, although some areas of E TX may gust to 20-25kts before
the convection arrives.
Zone update already out...grids will be available shortly.
15
&&
.PREV DISCUSSION... /issued 703 PM CDT Sat Nov 3 2018/
AVIATION...
VFR conditions will continue this evening, although cu cigs will
develop by mid-evening over E TX/Wrn LA and will quickly spread
NNE into SE OK/SW AR along a 45-50kt SSW LLJ ahead of a cold front
that will approach the region after 06Z. Sct convection has
already developed along the front early this evening over Cntrl
OK/extreme N TX, and will advance ENE into NE TX/SW AR between
04-06Z Sunday. Sct SHRA may develop ahead of the front and affect
portions of NE TX/SE OK/SW AR but should remain just W and N of
the TXK/TYR terminals, before the line of convection reaches E of
a MEZ, to TXK, to TYR line around 06Z. MVFR cigs may develop just
ahead of the convection late this evening, but MVFR cigs, reduced
vsbys, and locally gusty winds are expected with the convection.
The convection should affect the LFK/SHV terminals between 08-12Z,
and ELD/MLU between 09-14Z. MVFR and even IFR cigs may linger in
wake of the convection as it outruns the front, before these cigs
scatter out and lift with the cold frontal passage by mid to late
morning. Once VFR conditions return, they will persist through the
remainder of the TAF period under SKC or areas of thin cirrus. S
winds 7-15kts tonight, with gusts to 21kts over the Wrn sections
of E TX, will become WNW 7-11kts with the fropa Sunday. /15/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 58 67 52 76 / 90 50 0 20
MLU 58 68 51 76 / 80 90 10 20
DEQ 52 62 46 67 / 90 10 10 50
TXK 55 64 49 71 / 90 30 0 50
ELD 57 66 48 73 / 90 70 0 30
TYR 54 65 52 75 / 90 10 0 30
GGG 55 65 51 76 / 90 30 0 30
LFK 60 68 54 80 / 90 50 10 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
15