Area forecast discussion
National Weather Service Paducah Kentucky
1232 PM CDT Tuesday may 21 2013
Short term...(today through Thursday night)
issued at 215 am CDT Tuesday may 21 2013
Nearest term is dealing with remaining convection/tornados watch box.
In general...the trend is diminishing in strength/intensity as the
line sinks southward and eastward. A few healthy cells may
continue to pulse...however...and with a couple of outflow
boundaries working out of the northern and southern portions of
the convective line...we'll only drop watch box counties behind
the line.
The models show the convection moving east...weakening...and then
refiring this PM/evening as the upper level jet enters the
picture. Best lift/instability will be to our south...but a slight
risk of severe will continue. Would not be surprised to see a portion of
the County Warning Area/especially semo/swky/swil...included in a late day-early evening
watch box.
Associated surface wave opens up and lifts across MO/IL/in
tonight. This will drive the front and associated convection through
the area. Instability lessens with time/overnight but active
convection early in the period may extend through the
night...something to watch and a high pop/categorical mention is
warranted either way.
The upper trough/best height falls occur Wednesday and drive the
system through/to the east of US through Wednesday night. Probability of precipitation may even
linger through Thursday as 2ndary upper trough passage allows some
diurnal instability showers/storms to develop...particularly northern/eastern
portions forecast area. The system departs to the east by Thursday night...when
pleasantly cooler/drier air starts to overtake the column. 80s and
60s cool to 70s and 50s thereafter.
Long term...(friday through monday)
issued at 236 am CDT Tuesday may 21 2013
Dry and tranquil weather is expected late in the week with high
pressure ridging at the surface and aloft. Temperatures are likely
to remain in the 70s on Friday...and reach just shy of the seasonal
80 degree mark on Saturday. A warming trend will take place over the
weekend into early next week as low level flow becomes southerly on
the back side of departing high pressure.
Models continue to differ in their handling of a baroclinic zone
forecast to develop just north of the region early next week...and
thus with regard to precipitation chances as well. Both the Gem and
especially the GFS have been fairly consistent in keeping the
boundary and convective potential mainly north of the region as a
middle level ridge remains in place locally. On the other hand...the
European model (ecmwf) seems to suggest the boundary and associated precipitation
will meander south into the region by Monday. Given the rather poor
run to run consistency of the European model (ecmwf) and the presence of the middle
level ridge...prefer to steer the forecast in the direction of the
drier GFS at this time.
Will also keep temperatures above the initialized guidance blend
late in the period. This yields highs in the lower to middle 80s both
Sunday and Monday...with lows in the lower to middle 60s.
&&
Aviation...
issued at 1232 PM CDT Tuesday may 21 2013
VFR conditions expected through 00z. Scattered rain showers through 00z with
low VFR ceilings and MVFR visibilities possible. Increasing thunderstorm chances this
evening and overnight with predominant MVFR conditions likely.
Gusty winds and brief heavy rainfall possible with storms. Thunderstorms
will decrease west to east between 08z and 13z...with low VFR to
MVFR conditions persisting. Winds will be from the south to
southwest at 8 to 14 kts through the taf period...with gusts to 20
to 25 kts this afternoon.
&&
Pah watches/warnings/advisories...
Illinois...none.
MO...none.
In...none.
Kentucky...none.
&&
$$
Aviation...rst
