River Flood Warning 23, NWS St. Louis, MO

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
605 AM CDT Thu Mar 31 2022

.SHORT TERM...  (Through Late Friday Afternoon)
Issued at 256 AM CDT Thu Mar 31 2022

Precipitation is largely east and north of the CWA at this hour with
the surface low, cold front, and mid-level shortwave passing
downstream. Behind it, strong cold-air advection is slowly
slackening, and with drier air restricted further north and air near
saturation, temperatures remained steady overnight in the
mid/upper 30s. A secondary cold front across northern Missouri
associated with another shortwave across the central Great Plains
is stimulating a line of snow showers extending from central
Kansas up through Iowa, with some spurious snow showers out ahead
of it in western Missouri.

Temperatures today will struggle to rise above the low 40s in the
midst of overcast skies and the second cold front passing through
the CWA through the day. Ample mid-level forcing and a sufficiently-
cold column will allow for scattered rain/snow showers in central
and northeast Missouri to blossom and become slightly more
widespread during the late morning and early afternoon across east-
central/southeast Missouri and south-central Illinois. Snow
accumulations are not expected, as temperatures will stay around or
slightly above freezing near the surface. Any snowflakes mixed in
will likely melt as temperatures rise, albeit gradually, during the
day.

Showers will end from northwest to southeast when the upper-level
forcing is shunted east, allowing high pressure and upper-level
ridging to build into the region. Overnight, efficient radiational
cooling from clear skies and light winds will cool temperatures
below freezing across much of the area. Friday will be dry and
feature a warming trend when the high moves east and weak
southerly winds aid to bolster temperatures. The warmest highs
will likely be in central and southeast Missouri, where winds
shift out of the south first.

MRB

.LONG TERM...  (Friday Night through Wednesday)
Issued at 256 AM CDT Thu Mar 31 2022

Another mid-level wave will approach the region late Friday, causing
weak surface cyclogenesis and bringing the risk for light rain
Saturday. Deterministic guidance and the ensembles included in the
WPC Cluster Analysis continue to highlight two distinct areas of
precipitation on Saturday: one in the northern CWA where better mid-
level forcing will exist, and a second in southern Missouri where it
appears more appreciable moisture convergence along a cold front
will be. While light rain is certainly possible between these two
maxima, impacts will likely be very minor.

Ridging builds in and southerly winds return to the region quickly
on Sunday, sending temperatures back to around (if not slightly
above) normal. Ensemble probabilities of reaching 70F in central
Missouri are essentially non-existent for Sunday, though the
interquartile range of the NBM sits in the upper 60s to mid-70s. At
this point, I'm partial to the cooler solutions as the NBM ensembles
tend to be too warm during the spring. The NBM deterministic value,
in the upper 60s, is probably closer to reality. A mid-level
shortwave amidst the northern stream and attending surface low will
drag a cold front through the area on Monday. It looks likely that
the boundary will stall somewhere in southern Missouri, but exactly
when the boundary moves through and where it stalls is still
unclear.

A second, more amplified wave in the southern stream will develop a
low along this boundary and spark the potential for showers and
thunderstorms. The EPS/CMCE probabilities of exceeding 0.50" of rain
on Tuesday are largely confined to far southern Missouri and areas
south. The GEFS, however, brings the low (and associated
precipitation) further north. CIPS Severe Probability Guidance from
Saint Louis University, which uses the GEFS as input, paints an area
of non-negligible probabilities for severe weather into southern
Missouri. While a majority of the guidance suppresses the system to
the south, if that were to migrate north and come in line with the
GEFS, the potential for storms would increase. There are some
indications that storms along the stalled boundary may cause locally-
heavy rain as storm motion vectors appear parallel to the boundary.
It's far too soon to make any determinations on hazards with the
system, but it will be the focus going into next week.

MRB

&&

.AVIATION...  (For the 12z TAFs through 12z Friday Morning)
Issued at 556 AM CDT Thu Mar 31 2022

MVFR CIGs currently observed at the terminals will continue
through the morning and into the afternoon. Rain and snow showers
currently in northern and western Missouri will move through the
area today, forced by an upper-level low and weak cold front. VSBY
restrictions are possible if the terminals are directly impacted,
but confidence on the timing of these impacts is very low.

Showers will largely exit the terminals by the mid-afternoon, and
CIGs will begin to improve from west to east. Winds will begin to
weaken this evening as high pressure settles in place. Depending
on how efficiently we cool tonight, some fog may develop in the
river valleys and impact the low-lying terminals. Confidence in
this outcome is not high right now, but the potential will be
monitored.

MRB

&&

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

WFO LSX

Hazardous Weather Outlook
National Weather Service Saint Louis MO
258 AM CDT Thu Mar 31 2022

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-010800-
Adams IL-Audrain MO-Bond IL-Boone MO-Brown IL-Calhoun IL-Callaway MO-
Clinton IL-Cole MO-Crawford MO-Fayette IL-Franklin MO-Gasconade MO-
Greene IL-Iron MO-Jefferson MO-Jersey IL-Knox MO-Lewis MO-Lincoln MO-
Macoupin IL-Madison IL-Madison MO-Marion IL-Marion MO-Moniteau MO-
Monroe IL-Monroe MO-Montgomery IL-Montgomery MO-Osage MO-Pike IL-
Pike MO-Ralls MO-Randolph IL-Reynolds MO-Saint Charles MO-
Saint Clair-Saint Francois MO-Saint Louis City MO-Saint Louis MO-
Sainte Genevieve MO-Shelby MO-Warren MO-Washington IL-Washington MO-
258 AM CDT Thu Mar 31 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.

No hazardous weather is expected at this time.

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

There is a chance for thunderstorms across parts of the area on
Monday and Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated through tonight.

MRB

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
837 AM CDT THU MAR 31 2022

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

0700 AM     HEAVY RAIN       SAINT LIBORY            38.36N 89.71W
03/31/2022  M2.25 INCH       ST. CLAIR          IL   CO-OP OBSERVER

            STORM TOTAL RAINFALL.

&&

MAB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
838 AM CDT THU MAR 31 2022

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

0700 AM     HEAVY RAIN       WHITE HALL              39.44N 90.40W
03/31/2022  M1.88 INCH       GREENE             IL   CO-OP OBSERVER

            STORM TOTAL RAINFALL.

&&

MAB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
847 AM CDT THU MAR 31 2022

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

0830 AM     HEAVY RAIN       FOSTERBURG              38.97N 90.07W
03/31/2022  M2.10 INCH       MADISON            IL   TRAINED SPOTTER

            STORM TOTAL RAINFALL.

&&

MAB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
849 AM CDT THU MAR 31 2022

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

0800 AM     HEAVY RAIN       CRESTWOOD               38.56N 90.38W
03/31/2022  M2.59 INCH       ST. LOUIS          MO   PUBLIC

            STORM TOTAL RAINFALL. VIA TWITTER.

&&

MAB

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
915 AM CDT THU MAR 31 2022

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

0914 AM     HEAVY RAIN       2 NE HEMATITE           38.22N 90.46W
03/31/2022  M2.44 INCH       JEFFERSON          MO   TRAINED SPOTTER

&&