Area Forecast Discussion
Issued by NWS Paducah, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
000
FXUS63 KPAH 170802
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
302 AM CDT Mon Jul 17 2017

.SHORT TERM...(Today through Wednesday night)
Issued at 249 AM CDT Mon Jul 17 2017

Convection just outside FA is along a weak boundary that drapes
across our north and will still be lingering across the heart of
the FA today as we start to heat up. The models all pick up on it
and activate updrafts as dew points near 70 pool along it, and
some pva aloft rotates down the base of the mean trof just to our
east. The models all do kill it off the further south it goes as
it bumps into warmer air aloft, so we`ll keep a slight chance
mention over basically our northern 2/3 of the FA for primarily
the heating part of the day.

We get more and more under the influence of the upper dome of high
pressure heading thru the short term forecast period, with an H5
rise of 100 DM by 12Z Thursday. This will result in warming temps
throughout the column, and the overall subsidence in the
atmosphere will likely cap off any convective chances, or at least
make them silent, beyond this pm. We`ll warm temps accordingly,
which is at least a few degrees above the cool biased blended
temps everyone is observing/talking about. Triple digit heat
indices are still 24 hrs plus from showing up, and 48 hours plus
from showing up in earnest, so no real discussions taking place
yet on Advisory headline, although that is likely what we`ll end
up with by Tuesday or Wednesday, the beginning of a prolonged
period of triple digit heat indices.

.LONG TERM...(Thursday through Sunday)
Issued at 249 AM CDT Mon Jul 17 2017

Confidence continues to agree as models continue to show an increase
in continuity with their solutions.

The main threat continues to be the heat wave that will overtake the
region this week. A warming trend will start in the short term and
persist into or even through the long term. High pressure both at
the surface and aloft will continue to build into the region at the
start of the extended. This well could be an extended period of heat
index readings in the triple digits each day...possibly even
through the weekend. Do not expect to reach warning criteria but
due to the heats longevity will likely end up with at least a heat
advisory. The high pressure begins to drift off to the southeast
this weekend...but as usual the extended keeps pushing rain
chances off another 12 to 24 hours. So now the init keeps Saturday
dry. The rain chances do enter the forecast Saturday night and
Sunday. There could be an isolated storm over the north and west
would be the best chance. However the models keep 700mb between 10
and 13c degrees which is not a very good environment for storm
development. 700mb temps do dip below 10c a couple days in the
early morning which is also not ideal for spawning storms.

&&

.AVIATION...
Issued at 249 AM CDT Mon Jul 17 2017

Diurnal Cu bases should start out around 4-5K FT AGL and end up
maybe 5-6K FT AGL before dissipating late in the day. Vicinity
mentions of CB/storms is possible but not yet included at this
writing, with the overall Pop likely 20 percent or less. Patchy
fog is again a possible restrictor to early day vsbys but should
burn off quickly after the sun rises.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.