Flood Watch 4, NWS St. Louis, MO

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1218 PM CDT Thu Jul 7 2022

.SHORT TERM... (Through Friday Night)
Issued at 405 AM CDT Thu Jul 7 2022

Still a lot to deal with in the short term, between precipitation
chances and excessive heat over the next 24 to 48 hours. As of 08z,
the stalled front was south of the STL metro area with post frontal
showers and storms sliding east across the region, mainly along and
north of I-70.

Even though the front is south of I-70 and some precipitation/
clouds will linger through the morning hours today, feel that
temperatures south of I-70 will rebound enough to keep the
excessive heat warning going at this time.

Also, the latest deterministic models as well as CAMs indicate
that the stalled front will begin to lift northward as a warm
front this morning with an ongoing MCS over northwestern Missouri
tracking to the southeast along the front as the southerly low
level jet veers through the morning hours. MCS will gradually
weaken and move out of the forecast area by midday with a break in
the precipitation this afternoon. With the atmosphere taking
some time to recover after current activity exits and when another
complex develops and moves in tonight, feel that severe chances
are on the low side. However, can not rule out locally heavy
rainfall due to PWATS in excess of 2 inches, well above the 90th
percentile per latest GEFS/NAEFS, and warm cloud depth at least
1400 feet with efficient rainfall rates expected through Friday.

By tonight, upper level shortwave over the Northern Plains will
begin to lift northeastward towards the Great Lakes region, dragging
the main cold front through the region, eventually exiting by
sometime Friday night. In the meantime, more organized convection
will fire up tonight in the form of an MCS over southwestern Iowa
then track to the east and southeast across the forecast area through
Friday.

As for the issue of possibly extending the Excessive Heat Warning
for portions of southeast Missouri on Friday, it will depend on
the timing of the cold front and precipitation. So day crew will
need to keep an eye on later model trends to see if the warning
needs to be extended.

Byrd

.LONG TERM... (Saturday through Wednesday)
Issued at 405 AM CDT Thu Jul 7 2022

After the precipitation exits the region on Saturday, surface
ridge will build in with dry and near normal temperatures for the
rest of the weekend.

Beyond the weekend as the surface ridge moves off to the east,
southerly flow will return to the region with temperatures warming
back up into the 90s on Monday. Some differences among the
deterministic and ensemble model runs with active pattern
developing. Thus chances of rain returns once again, but timing,
location and strength of each system is hard to pin down. For now
stuck with the latest NBM solution with precipitation moving in
Monday night through Tuesday at this time.

Byrd

&&

.AVIATION...  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1210 PM CDT Thu Jul 7 2022

While some isolated storms cannot be ruled out late this afternoon
and early evening, mostly dry weather is expected until later
tonight. A surface low is forecast to move along a stalled frontal
boundary tonight providing a chance of more widespread shower and
thunderstorm activity. Similar to earlier today, the best chances
should be in northeast Missouri and west-central Illinois
including at KUIN. As the boundary moves further to the southeast
late tonight into early Friday morning, storms should weaken and
lessen in coverage so there is more uncertainty in storms
impacting the central Missouri and metro St. Louis terminals.

Dry conditions are forecast for the terminals toward the end of
the TAF period with winds veering with time as the cold front
progresses into southeast Missouri and southwest Illinois. Some
MVFR ceilings are likely behind the front in northeast Missouri
and west-central Illinois Friday morning as well so added a BKN025
in at UIN.

Gosselin

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Excessive Heat Warning until 11 PM CDT this evening for Crawford
     MO-Franklin MO-Gasconade MO-Iron MO-Jefferson MO-Madison MO-
     Osage MO-Reynolds MO-Saint Francois MO-Sainte Genevieve MO-
     Washington MO.

IL...Excessive Heat Warning until 11 PM CDT this evening for Monroe
     IL-Randolph IL.

&&

WFO LSX

Hazardous Weather Outlook
National Weather Service Saint Louis MO
410 AM CDT Thu Jul 7 2022

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-081200-
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Adams IL-Brown IL-Pike IL-
Calhoun IL-Jersey IL-Madison IL-Saint Clair-Monroe IL-Knox MO-
Lewis MO-Shelby MO-Marion MO-Monroe MO-Ralls MO-Pike MO-Boone MO-
Audrain MO-Moniteau MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-
Lincoln MO-Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-Crawford MO-
Washington MO-Saint Francois MO-Sainte Genevieve MO-Iron MO-
Madison MO-Reynolds MO-
410 AM CDT Thu Jul 7 2022

This Hazardous Weather Outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Today and tonight.

An Excessive Heat Warning remains in effect for areas along and
south of I-70 through this evening with heat indices between 100 and
110 degrees.

There is a chance of thunderstorms through tonight, mainly along and
north of I-70. Locally heavy rainfall is possible.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

There is a chance of thunderstorms over parts of the area through
Saturday. There is another chance of thunderstorms Monday night
through Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated through tonight.

Byrd

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
1214 PM CDT THU JUL 7 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1214 PM     HEAVY RAIN       GILLESPIE               39.13N 89.82W
07/07/2022  M2.40 INCH       MACOUPIN           IL   TRAINED SPOTTER

&&

CARNEY

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
1255 PM CDT THU JUL 7 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1255 PM     HEAVY RAIN       5 SW STOUTSVILLE        39.50N 91.91W
07/07/2022  M1.20 INCH       MONROE             MO   TRAINED SPOTTER

&&

CARNEY