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000 
FXUS63 KJKL 290319 AAB
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1119 PM EDT Fri Apr 28 2017

.UPDATE...
Issued at 1105 PM EDT FRI APR 28 2017

The focus for shower and thunderstorm activity continues to be
near the Ohio River near a warm front. Steering flow should keep
the activity generally in this corridor. A few showers or a stray
thunderstorm is possible in the far north overnight, but most
locations should remain dry. Valley minimum temperatures were
lowered a bit to account for nocturnal inversion that has set up
in the deeper valleys.

UPDATE Issued at 835 PM EDT FRI APR 28 2017

The mid level cap has generally held across southeast KY this
evening. With mid level height rises, loss of daytime heating, and
lower dewpoints in far southeast KY from deeper mixing and
downslope flow off of the Cumberland Mountains and threat of
strong to severe thunderstorms across East KY is diminishing.
Recent radar, satellite and short term convective allowing models
indicate that the primary risk for severe weather for the
remainder of the evening and into the overnight will probably be 
near the OH River and north near the current position of the warm
front. Scattered showers and an isolated strong to possibly 
severe thunderstorm still cannot be ruled out this evening 
generally along or north of I 64. Across the remainder of the 
region, the overnight should be mainly dry.

&&

.SHORT TERM...(This evening through Saturday night)
Issued at 400 PM EDT FRI APR 28 2017

Quite a bit of uncertainty still exists in the model data
regarding convective initiation and evolution this afternoon
through late this evening across eastern Kentucky. The best guess
for now is that storms that will be forming to our west and 
southwest will eventually move into our northwestern counties late
this afternoon, and will move across the area generally north of 
the Hal Rogers Parkway and Highway 80 corridor through early 
tomorrow morning. Any storm that does make into the area will have
the potential of producing large hail, damaging wind gusts, and 
perhaps an isolated tornado. A severe weather watch may be
necessary to begin the evening shift. The first showers and 
storms should move into our northwestern counties around 22Z, and 
will move east across the northern half of the forecast area 
overnight.

Temperatures should continue to run well above normal, with
nightly lows only bottoming out in the 60s tonight and tomorrow
night, and highs maxing out in the upper 80s and lower 90s on
Saturday. Winds should be primarily out of the south at 7 to 
12 mph through the period.

.LONG TERM...(Sunday through Friday)
Issued at 400 PM EDT FRI APR 28 2017

The models are still in good agreement aloft for the bulk of the 
extended period. They all depict a strong ridge through the 
southeast portion of the nation with broad southwest flow ahead of a 
deep closed low moving into the Texas Panhandle early Sunday. This 
low will further deepen and lift into the mid Mississippi Valley by 
Monday morning with the GFS a bit quicker and more northerly than 
the ECMWF. Both are quite deep, though, with height falls spreading 
through Kentucky. This bowling ball of a low then barrels into the 
western Great Lakes by Tuesday morning similar, but still with the 
GFS leading the ECMWF. The Canadian solution is similar to the 
others lending confidence to the consensus solution at least through 
mid week. As this low transitions past to the north the core of its 
energy will swing through eastern Kentucky Monday morning with 
another significant node passing early Tuesday. The pattern will 
then slowly deamplify through Wednesday with more zonal type of flow 
through the region before the next trough starts to take shape over 
the southern High Plains. This trough quickly sinks to the south and 
reaches the Gulf Coast by Thursday afternoon before wrapping up more 
and closing off over the Deep South by 12z Friday - quickest and 
furthest east in the ECMWF than the others. This low will then 
slowly traverse the Deep South off to the east - maintaining the low 
heights and cyclonic mid level flow over eastern Kentucky. Given the 
decent agreement for the extended have greater than normal 
confidence in the extended forecast from the blend.  

Sensible weather will feature a warm and humid end to the weekend 
ahead of a drying out cold front. After highs in the upper 80s most 
places on Sunday afternoon the front will move through by Monday 
morning with a threat for storms as well as ushering in a cooler and 
drier air mass. This air quickly gets replaced by another surge of 
moisture from the south starting on Wednesday as a warm front stalls 
nearby with a concern for storms and heavy rains that afternoon 
through Thursday. The developing sfc low to our south for the latter 
part of the week will keep the threat of showers and a stray storm 
in the forecast through Thursday followed by mainly just showers and 
seasonably cool temperatures - a far cry from those that we will see 
this weekend. 

Raised temps a tad on Sunday with more sunshine expected and being 
rain free. Did make some minor adjustments to temperatures each 
night - particularly for ridge to valley differences early Sunday 
night and again Tuesday night. Also, fine tuned the PoPs to tighten 
them up with the fropa on Monday morning and heading into the 
Wednesday system. 

&&

.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 835 PM EDT FRI APR 28 2017

Shower and thunderstorm activity during the first 12 to 15 hours 
of the period should mainly be confined to locations near a warm 
front located near the OH River. KSYM could experience a few 
showers or a tsra and VCTS has been used there for the first 
several hours of the period. If KSYM were to experience a direct 
hit from a thunderstorm a period of IFR VIS and or CIGS will be 
possible along wind wind gusts up to 30KT. COnfidence in this 
however is too low to include attm. Otherwise, upper level ridging
should keep convection at bay with VFR expected. Winds through 
the period should average out of the south at 5 to 10 mph.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

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