Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 300632
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
132 AM CDT Sat Aug 30 2014
.SHORT TERM...(Tonight through Sunday night)
Issued at 316 PM CDT FRI AUG 29 2014
Shower and thunderstorm coverage should increase from the west late
this afternoon and evening with the approach of an upper level
trough from the plains. Until then, isolated to widely scattered
convection could pop up just about anywhere across our CWA.
Precipitation chances continue to increase area wide through
Saturday night with the upper trough axis remaining to our west
combined with deepening moisture streaming across the region.
Although widespread severe weather is not expected at this time,
precipitable water values will be in excess of 2 inches both
Saturday and Saturday night, so at this time it appears that locally
heavy rainfall will be the primary threat.
Latest model runs are in decent agreement in showing the upper
trough flattening/shearing out and whats left of it moving off to
the east on Sunday, therefore decreased precipitation chances from
the west on Sunday. Sunday night there may be small precipitation
chances from the aforementioned system lingering over our far
southeast counties as well as small precipitation chances over the
western and northwestern sections along the leading edge of a
system moving out of the plains.
Although there will be little change to dewpoints in the short term,
temperatures will return to near normal readings for both Saturday
and Sunday. This scenario will keep relative humidities elevated,
but afternoon heat indices should make outdoor work and other
activities much easier to handle.
.LONG TERM...(Monday Night through Friday)
Issued at 126 AM CDT SAT AUG 30 2014
At the beginning of the long term portion of the forecast, a
developing frontal system will enter our northern and western
counties, as a long wave trof drops down across the upper MS
valley. The boundary then lays out across the area Tuesday, and
goes quasi-stationary, before returning as a warm sector boundary,
Tuesday night into Wednesday. As a result, Pops range from the mid
to high chance category thru Wednesday.
After that, broader high pressure over the southern U.S. results
in sufficient height rises in our area to diminish daily Pops to a
slgt chance mention, particularly for the heat of the day
possibility of storms, through Thursday. Friday sees the High
effectively silence pops out of mention, though an isolated chance
possibility cannot be completely ruled out.
Temps look to hold near summer like values within just a few
degrees of 90 and 70 for highs and lows through the entire
extended portion of the forecast.
Issued at 1159 PM CDT FRI AUG 29 2014
Showers and possibly a few storms will continue to move across
southeast Missouri overnight...but they will struggle to cross the
Mississippi River as they move into more stable air. As a
disturbance in the upper levels of the atmosphere approaches our
area...the activity will eventually reach all the taf sites around
12z. Instability will be quite weak by that time...so predominantly
showers are expected. Thunder could occur at any time Saturday...but
it was not worth a 12 hour period of thunder in the tafs. Mainly
mvfr vsbys are expected in the more widespread showers...but vsbys
will likely be highly variable since the showers could be heavy. A
break in the shower activity appears likely Saturday evening in the
wake of the upper level disturbance.