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Area forecast discussion 
National Weather Service Shreveport la
1104 am CDT Thursday Oct 2 2014

Discussion...
models initializing quite well with respect to the positions of
the approaching shortwave. Kshv radar showing decent coverage of
convection across parts of deep East Texas/north la...which appears to be
well covered by most of the models...NAM excluded. This should
continue as the shortwave/cold front approach from the west/northwest
today...bringing the good possibility of severe storms to NE Texas/southeast
OK by this afternoon. Forecast package is in pretty good shape. Have
upgraded probability of precipitation across deep East Texas/north la to 40 percent...but no other
changes were made. Updated products will be out shortly. /12/

&&

Previous discussion... /issued 749 am CDT Thursday Oct 2 2014/

Discussion...

MVFR/IFR flight categories due ceilings and visibility restrictions
will prevail into late morning to middle day lifting to VFR. Patchy light
rain and embedded showers this morning over parts of East Texas
and lower northwest and north central Louisiana...these could affect
klfk and kmlu. VFR should continue into the early evening before
returning to MVFR with scattered showers and lowering
ceilings...then to IFR with the approach and passage of a cold
front with locally heavy rain and convection. MVFR/IFR categories
will carry over into the remaining terminal forecast period ending
around 03/12z. Winds will be south 10-15 knots today with a
tightening pressure gradient over the area especially for East
Texas and adjacent sections of northwest Louisiana and southwest
Arkansas. Winds will remain around 10 knots until frontal passage
when winds become more westerly then northwest. With building high
pressure into the area on Friday winds will be northwest to north
13-17 knots. /06/

Previous discussion... /issued 505 am CDT Thursday Oct 2 2014/

Discussion...
active weather scenario continues to take shape for later this
evening as the large-scale trough begins to emerge along the eastern
slope of The Rockies with a strong short wave rounding the base
and entering the plains early this morning. This upper trough and
accompanying short wave will act to speed up a strong cold front
currently located over the OK/Texas Panhandle region and up across
central and eastern Kansas...where a warm front extends eastward into MO/IL.
Looking southward across our region...the pump is already primed ahead
of the approaching cold front with a very moist and humid air mass
in place. Dew points are running in the low to middle 70s area wide
with increasing southerly flow throughout the day in response to
the intensifying surface low over the Texas Panhandle. Abundant stratus
has developed and spread northward this morning but this will not
prevent temperatures from quickly jumping into the lower 90s later
this afternoon at most locations with some scattered showers/thunderstorms
developing ahead of the front in an increasingly unstable air
mass. Chance probability of precipitation should suffice for today over much of the region
but increase to likely over our far northwestern County Warning Area by late afternoon.

As we look to ahead this evening...the cold front will begin to
enter our far western counties in NE Texas and southeast OK as the upper trough
and short wave eject rapidly northeastward into the midsection of the
country. The front will encounter a very moist and unstable warm
sector over our region with sb convective available potential energy near 2000 j/kg and a southwesterly ll
jet of 30-40 kts. This should allow for a rapidly intensifying
squall line to develop and shift eastward through the evening hours.
Convective outlook from Storm Prediction Center continues to paint a large slight risk
area for severe weather later today and especially tonight as the
front accelerates into the region. The primary threat will be in
the form of damaging straight-line winds with the squall line as
unidirectional flow will dominate initially but threats of large
hail and isolated tornadoes are also included in this slight risk
as deep layer shear will begin to increase as the short wave moves
overhead. Expect the front to race eastward through early Friday
morning with the line of showers and thunderstorms generally along or just
ahead of the front. Severe threat will end toward daybreak across
our eastern areas as the front exits to the east.

The first weekend in October will indeed feel very fall-like
behind the front with lows ranging through the 40s area wide on
Saturday morning. Highs will also run below climatology on Saturday but
gradually moderate back to near normal by Sunday and even above
normal to start next week as a weak front drops south and may be
enough to generate some scattered showers/thunderstorms by middle week. /19/

&&

Preliminary point temps/pops...
shv 92 63 83 48 79 / 30 80 10 0 0
mlu 91 70 83 47 76 / 40 70 20 0 0
deq 88 56 78 40 74 / 60 80 10 0 0
txk 90 61 79 45 75 / 40 80 10 0 0
eld 90 63 81 43 74 / 30 80 10 0 0
tyr 92 60 82 48 79 / 40 80 10 0 0
ggg 93 62 83 46 78 / 30 80 10 0 0
lfk 93 66 84 48 80 / 30 70 10 0 0

&&

Shv watches/warnings/advisories...
Arkansas...none.
La...none.
OK...none.
Texas...none.
&&

$$

12

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