Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL5
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 275
NWS Storm Prediction Center Norman OK
615 AM CDT Tue May 21 2024
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and southern Iowa
* Effective this Tuesday morning and afternoon from 615 AM until
100 PM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated large hail events to 1.5 inches in diameter possible
A tornado or two possible
SUMMARY...Clusters of thunderstorms -- including an organized bowing
complex initially over eastern NE -- will pose a threat mainly for
severe gusts while crossing the watch area from west to east. A
tornado or two cannot be ruled out, especially near an outflow
boundary draped across central/south-central IA. Isolated large
hail is possible. This is a precursor to the main severe-weather
threat expected later today, for which we have a "Moderate Risk"
outlook.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 80 miles west of Des
Moines IA to 25 miles south southeast of Cedar Rapids IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 274...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
26045.
...Edwards
SEL5
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 275
NWS Storm Prediction Center Norman OK
615 AM CDT Tue May 21 2024
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and southern Iowa
* Effective this Tuesday morning and afternoon from 615 AM until
100 PM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated large hail events to 1.5 inches in diameter possible
A tornado or two possible
SUMMARY...Clusters of thunderstorms -- including an organized bowing
complex initially over eastern NE -- will pose a threat mainly for
severe gusts while crossing the watch area from west to east. A
tornado or two cannot be ruled out, especially near an outflow
boundary draped across central/south-central IA. Isolated large
hail is possible. This is a precursor to the main severe-weather
threat expected later today, for which we have a "Moderate Risk"
outlook.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 80 miles west of Des
Moines IA to 25 miles south southeast of Cedar Rapids IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 274...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
26045.
...Edwards
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW5
WW 275 SEVERE TSTM IA 211115Z - 211800Z
AXIS..60 STATUTE MILES NORTH AND SOUTH OF LINE..
80W DSM/DES MOINES IA/ - 25SSE CID/CEDAR RAPIDS IA/
..AVIATION COORDS.. 50NM N/S /32NE OVR - 4ENE IOW/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..65 KNOTS.
MAX TOPS TO 550. MEAN STORM MOTION VECTOR 26045.
LAT...LON 42399522 42419154 40689154 40659522
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU5.
Watch 275 Status Report Messages:
STATUS REPORT #1 ON WW 275
VALID 211545Z - 211640Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 NNE SDA
TO 10 SW DSM TO 25 NNE OXV TO 10 NW ALO.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 868
..MOSIER..05/21/24
ATTN...WFO...DMX...DVN...
&&
STATUS REPORT FOR WS 275
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC003-007-011-013-019-031-039-051-053-055-087-095-101-103-105-
107-113-117-121-123-125-135-157-159-171-173-175-177-179-181-183-
185-211640-
IA
. IOWA COUNTIES INCLUDED ARE
ADAMS APPANOOSE BENTON
BLACK HAWK BUCHANAN CEDAR
CLARKE DAVIS DECATUR
DELAWARE HENRY IOWA
JEFFERSON JOHNSON JONES
KEOKUK LINN LUCAS
MADISON MAHASKA MARION
MONROE POWESHIEK RINGGOLD
TAMA TAYLOR UNION
VAN BUREN WAPELLO WARREN
WASHINGTON WAYNE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (20%)
|
Probability of 1 or more strong (EF2-EF5) tornadoes
|
Low (10%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (50%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (50%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (30%)
|
Probability of 1 or more hailstones > 2 inches
|
Low (10%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (70%)
|
For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The "Low" category contains probability values ranging from less than 2%
to 20% (EF2-EF5 tornadoes), less than 5% to 20% (all other probabilities),
"Moderate" from 30% to 60%, and "High" from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.
weather.gov 
@NWSSPC
