Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 262000
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
300 PM CDT Sun Oct 26 2014
.SHORT TERM...(Tonight through Tuesday night)
Issued at 300 PM CDT SUN OCT 26 2014
The warm front is draped across the area this afternoon, with
dewpoints in the lower and middle 60s southwest of it, and 30s and
40s northeast of it. Local radar`s VAD wind profiles indicate that
the front is quite shallow and, therefore should push through the
remainder of the area by 12Z Monday. With loss of mixing,
dewpoints should quickly recover northeast of it this evening.
Could see temperatures drop quickly in the northeast this evening,
before increasing with the warm frontal passage. Did not go with a
non-diurnal trend overnight up there, but it may be needed with
updates this evening. Did try to account for the cooling in the
low temperature forecast a bit. Elsewhere, would expect lows to be
at or above consensus guidance.
Gusty south southwest winds will result from a tightening gradient
and strong mixing. This will lead to a very warm day with
dewpoints mixing through the 50s through the day. Went close to
persistence for highs which was more reflective of the warmer MAV
guidance. The winds will stay up through the night, so figure on a
very mild night Monday night. Went above consensus again.
The 12Z GFS continues to be the most progressive with our next
cold front/storm system, and it seems to be on the right track.
The 12Z ECMWF is quicker to bring in the precipitation and hangs
on to it in the southeast into Tuesday evening. Meanwhile the NAM
has the best of both worlds, being slow to bring in the
precipitation and slower to push it out. Went with the slower
onset of precipitation, closer to 12Z, but decided there was no
harm in keeping some lower PoPs in the southeast Tuesday night.
PoPs are categorical for the main band of precipitation.
The models all seem less robust with even elevated instability
with the system, but they do still have some. Will keep a chance
of thunderstorms mentioned, but am not as excited about it as
yesterday. With less instability expected, QPF will likely end up
lighter, would not be surprised to see a quarter inch or less over
much of the area.
Looks like a decent clearing trend behind the precipitation
Tuesday afternoon in the west, so figure on temperatures
recovering a bit closer to the warmer MAV guidance. With some
cloud cover still streaming across at least southern portions of
the area, and light winds, decided to stay close to consensus of
statistical guidance for lows Tuesday night.
.LONG TERM...(Wednesday through Sunday)
Issued at 300 PM CDT SUN OCT 26 2014
The GFS and ECMWF ensemble means were in decent agreement with the
overall mid/upper pattern scenario in the extended. However, smaller
details in the med range model solutions continue to be tougher to
nail down. Whether or not it occurs, measurable pcpn should be
Mid-week, the PAH forecast area will be under the influence of dry
high sfc pressure and quasi-zonal flow aloft. Meanwhile, the
mid/upper flow across the CONUS is progged to begin to undergo
significant amplification as longwave energy digs into wrn Canada
and adjacent parts of the wrn U.S. coast. The increasingly nwrly
flow across the central CONUS should contain a shrtwv energy
impulse, with very little sfc reflection, moving se across our
region by Thu night. Dry air in place at the low levels will
probably preclude measurable rainfall from occurring initially, but
the initialization blend continued to have a signal for some kind of
light measurable rainfall (early?) on Fri. For this forecast
package, we will go with a slight chance for the Pennyrile region of
KY, swrn IN, and parts of sern IL.
Another surge of dry high pressure air is expected to sweep into the
region for the weekend under fast nwrly flow aloft. Dewpoints are
expected to plunge into the 30s and upper 20s Sat/Sun. Sat afternoon
and Sun morning should be the coolest period, with highs only in the
50s and lows near freezing, especially east of the MS River. Frost
will be most likely Sun morning due to lighter sfc winds.
Issued at 1218 PM CDT SUN OCT 26 2014
A weak warm front will move northeast through the area by daybreak
Monday. A light southeast wind this afternoon will become
southerly as the boundary passes. Guidance hints at some low
clouds with the front at KEVV and KOWB late tonight, but really
don`t see enough moisture to support it at this time. There should
be enough wind to prevent fog formation tonight. Strong southerly
winds will develop shortly after sunrise, and by late morning all
sites should be gusting well over 20kts.