Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Shreveport la
1012 PM CDT Tuesday Mar 31 2015
scattered convection continues to develop this evening over eastern
OK...with more isolated convection having developed farther east
across central Arkansas...along a stationary front from near okc...to S
of okm...to fsm...then east across north central Arkansas. Convergence continues
to focus scattered convection moreso farther west along this boundary across
eastern/cntrl/wrn OK...where MLCAPES are maximized between 1500-2000
j/kg as of mid-evening. Per the 00z koun/klzk radiosonde observations...no capping
inversion was evident near these boundaries...although capping does
increase farther S across North Texas and northern la /per the 00z kfwd/kshv
raobs/...and should remain in place overnight thus preventing much
in the way of southward development. There was also an outflow boundary
that developed from earlier convection over eastern Arkansas late this
afternoon...that backbuilded SW to just west of a pbf...to llq line
before becoming stationary...thus any convection tonight /albeit
limited/...should be confined to mainly extreme NE Texas/southeast OK/SW Arkansas
near these boundaries and the higher axis of instability/weaker cin.
Have tapered back probability of precipitation this evening...but did retain low chance
probability of precipitation for southeast OK/adjacent SW Arkansas should the SW OK convection continue
to shift east along the convergent surface boundary. Did taper probability of precipitation down to
slight chance along the I-30 corridor of NE Texas...as well as the
remainder of SW Arkansas...and dropped mention of probability of precipitation farther S for the
night. Still expecting low stratus to develop/spread north across much
of the region late...thus limiting the temperature fall even with light S
winds. Only minor tweaks were needed to the forecast min
temperatures per the 02z observation...but overall...most areas should fall in the
lower 60s by daybreak Wednesday.
Updated zones already out...grids will be available shortly.
Previous discussion... /issued 711 PM CDT Tuesday Mar 31 2015/
MVFR still at ktxk until sunset...then sky clear everywhere in the County Warning Area.
S/SW surface winds are slacking gusts now and low level flow overnight
will bring in more IFR/MVFR ceilings around or shortly after daybreak
with improvement to VFR by 18z. Look for a chance for thunderstorms
arriving in East Texas by 21z and area wide overnight as an upper low
moves over the middle south. At this time...our climb winds are deep SW flow
10-20kts...then veering to west-northwest 20-50kts aloft with 65kts by fl300.
Little change aloft behind the upper low until frontal passage 04/00z. /24/
Preliminary point temps/pops...
shv 61 80 64 81 / 5 30 20 30
mlu 61 81 64 82 / 10 20 20 30
deq 60 76 61 77 / 30 40 40 30
txk 62 77 63 78 / 20 30 30 30
eld 60 79 63 80 / 20 20 20 30
tyr 63 79 65 81 / 10 40 30 30
ggg 62 80 64 81 / 10 30 30 30
lfk 63 81 65 83 / 5 30 30 30