684
FXUS63 KLSX 152328
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
628 PM CDT Sat Jun 15 2024

.KEY MESSAGES...

- Temperatures are expected to remain above normal through next week.
  Sunday and Monday will be the warmest days with peak heat index
  values in the upper 90s to 105 degrees.

- There is a low chance (20 percent) of showers and thunderstorms this
  evening over central Missouri. There are low chances (20-40
  percent) for afternoon showers and thunderstorms mainly Monday
  through Wednesday.


&&

.SHORT TERM...  (Through Late Sunday Night)
Issued at 225 PM CDT Sat Jun 15 2024

Regional radar is showing a small area of showers and thunderstorms
over north central Missouri that is slowly moving to the northeast
this afternoon.  This activity will likely diminish as it will be
moving into an area of rapidly decreasing MUCAPE per the SPC
mesoanalysis. Some of the CAMS are showing isolated convection over
central Missouri into the early evening, so held on to a slight
chance of thunderstorms through this evening.

Attention then turns to what will be the warmest day of the year so
far with highs climbing into the middle to upper 90s with heat
indices ranging from the upper 90s to 105.  It will be warm start to
the day with lows tonight ranging from the upper 60s to mid 70s.
Surface winds will turn out of the south-southwest tomorrow morning
with 850mb temperatures around 20C which favors a warmer day. The
NBM deterministic highs tomorrow are slightly warmer than the MOS
guidance, which supports our going forecast. Otherwise expect a
mainly sunny day with little chance of rain.

Britt

&&

.LONG TERM...  (Monday through Next Saturday)
Issued at 225 PM CDT Sat Jun 15 2024

There is still good agreement between the global models and the LREF
that the large upper high over the East Coast will gradually expand
westward into the central CONUS by late next week.  Model guidance
is also showing moisture returning off the Gulf of Mexico on the
back side of the upper high that won`t get cut off until the high
builds back into the area later in the week.  Ensemble members are
still supporting a chance (20-40%) of mainly daytime showers and
thunderstorms Monday into Wednesday with lower chances late in week.

Monday looks like another warm day with highs in the middle 90s with
some locations having heat indices exceeding 100 degrees, mainly
around the St. Louis metro area.  Then there will be an increase in
clouds and rain chances that will cause highs to be slightly lower
during the middle of the week before highs are forecast to go back
up into the middle 90s Friday and Saturday as the upper high moves
back over the area. Confidence in the temperature forecast is
highest on Monday when the NBM IQR is only 5 degrees, but lowers
Tuesday into Thursday as the IQR widens to 6-8 degrees.

Britt

&&

.AVIATION...  (For the 00z TAFs through 00z Sunday Evening)
Issued at 628 PM CDT Sat Jun 15 2024

VFR conditions continue. Light winds overnight increase a bit on
Sunday.

Kimble

&&

.CLIMATE...
Issued at 328 AM CDT Sat Jun 15 2024

Daily High Temperature Records:
                 |=== June 16 ==|=== June 17 ==|
St. Louis (KSTL) | 100 F (1952) |  99 F (1944) |
Columbia  (KCOU) |  99 F (2006) | 100 F (1936) |
Quincy    (KUIN) | 102 F (1936) | 103 F (1918) |


&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$

WFO LSX