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Area forecast discussion...updated 
National Weather Service Little Rock Arkansas
647 PM CDT Wednesday Sep 17 2014

Aviation...
convection will remain across the west this evening..and have thunderstorms in the vicinity
in the two western tafs through the evening hours. Short term
guidance has a break in the convection...before another system
potentially develops overnight. Due to low confidence...have vcsh
across the north. MVFR conditions will develop across the northern
half with the low level moisture overnight...and may become IFR.
&&

Previous discussion... /issued 149 PM CDT Wednesday Sep 17 2014/

Short term...tonight through Saturday night

Area of rain showers/thunderstorms and rain ongoing across southern MO is beginning to accelerate
as the strongest cells along the western half of this complex drops south
into Arkansas. Several of the recent runs of the high-res hrrr have done a
reasonable job on these features...and show this activity dropping
generally south throughout the afternoon hours. Expecting this
activity to generally follow the higher instability axis across
the western half to two-thirds of the state where most unstable cape
values are on the order of 1-3k j/kg at this hour. As a result...do
have highest probability of precipitation through middle afternoon over the northern and northwestern
sections of the County Warning Area...then dropping south to SW over time later
this afternoon. The hrrr solutions even keep this activity going
into the southwestern sections of the area by this evening...so have
generally followed this trend with probability of precipitation. However...do drop probability of precipitation
over time as uncertainty in coverage an intensity increases by
late this evening regarding this ongoing convective activity.

Beyond this evening...the timing and placement of what may be the
next upper disturbance moving over the state becomes a bit
uncertain. Earlier short term model solutions have the next wave
moving over late tonight into Thursday morning...but this may not be the
case with the ongoing activity and its expected path. The next wave
may be delayed a bit longer...but may also not be as intense as
earlier expected. With that said...continue with generally location
of chance probability of precipitation for much of Thursday...but have decreased probability of precipitation some as a
result of the uncertainty of when/where the next wave may move.

By Friday into early Sat...an upper ridge will move over the
region...decreasing probability of precipitation and increasing temperatures across the state. By
late in the period though...have increasing probability of precipitation with the approach
of an upper low or the remnants of Odile as they approach from the
west/NW.

Long term...Sunday through Wednesday

A cold front will be making its way through the state at the start
of the long term...with some rain chances making their way into the
area through Monday afternoon. Though...latest model solutions seem
less ambitious about widespread rainfall in the state.

As rain chances dissipate by Monday...cooler air will filter into the
state. Both high and low temperatures will be fairly normal to
slightly below normal for the latter part of September in Arkansas.
Winds will generally be out of the north through the extended period
and a cool northwest flow aloft will be in place.
&&

Lzk watches/warnings/advisories...none.
&&

$$

Aviation...58

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