Area Forecast Discussion
Issued by NWS Little Rock, AR

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FXUS64 KLZK 200902
AFDLZK

Area Forecast Discussion
National Weather Service Little Rock AR
402 AM CDT Wed Sep 20 2017

.SHORT TERM...Today Through Thursday Night
The large scale pattern remains fairly unchanged this morning with
upper ridging still firmly entrenched from the Gulf northeastward
to the Great Lakes. Under this regime, warmer than average
temperatures are expected through the period with most locations
reaching the upper 80s and low 90s this afternoon and again
Thursday afternoon. Expect overnight temps in the 70s with a
moist, muggy atmosphere in place.

Hi-res guidance shows a shortwave trough nosing in through the
larger upper ridge this afternoon. Considering the amount of
available energy...MUCAPE values exceeding 2000-3000
J/kg...isolated thunder is possible. However, larger scale
subsidence should act to limit areal coverage of convection if it
develops at all. Better upper energy associated with the
shortwave trough will pass to our south, so fairly confident
leaving very low end PoPs through the period. A tightening
pressure gradient will increase southerly flow with occasionally
gusty winds during the afternoons.

&&

.LONG TERM...Friday Through Tuesday Night
And the heat goes on. (Sorry, I couldn`t resist).

Evident in upper air analysis as well as satellite data this morning
is troughing starting to be carved out in the upper reaches of the
Ohio Valley to the west of Tropical Storm Jose. This will expand
southward into the Tennessee and lower Mississippi Valley, and
toward the Gulf by the end of the week. To the north of that,
persistent, irritating longwave ridge that will not seem to die
will remain for the time being.

So, while large-scale convection will be suppressed over much of
the region due to our not-so-friendly ridge, presence of the trough
near us will at least allow for isolated/widely scattered showers
and storms through the weekend. These will largely be diurnal, and
develop as daytime heating interacts with any mesoscale features.

As Jose eventually diminishes, and Maria moves northward, the ridge
will dampen out. Remaining upper low/trough will be absorbed into
Maria, with ridging building over the western Gulf.

What does this mean for us, you ask? Well, it will make the flow
over us a little more quasi-zonal, which will give momentum to a
frontal boundary that will be stalled in the plains. The boundary
will affect us just beyond the end of the period, with rain chances
increasing. Cooldown? Yes, it looks that way. Not as much as I would
like, mind you, but temperatures should get back closer to where we
would expect them this time of year. Oh well. It`s a start.

&&

.PRELIMINARY POINT TEMPS/POPS...
Batesville AR     91  72  91  70 /  20   0  10   0
Camden AR         91  73  91  71 /  10   0  10   0
Harrison AR       90  70  89  68 /   0   0  10   0
Hot Springs AR    91  72  90  71 /  10   0  10   0
Little Rock   AR  92  73  91  72 /  10   0  10   0
Monticello AR     91  73  91  72 /  10   0  20   0
Mount Ida AR      91  72  89  70 /   0   0  10   0
Mountain Home AR  91  70  91  70 /  10   0  10   0
Newport AR        91  71  91  71 /  10   0  10   0
Pine Bluff AR     91  73  91  71 /  10   0  10   0
Russellville AR   93  72  91  71 /  10   0  10   0
Searcy AR         91  71  91  71 /  10   0  10   0
Stuttgart AR      91  72  91  71 /  10   0  10   0
&&

.LZK Watches/Warnings/Advisories...NONE.
&&

$$


Aviation...99


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