Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL1
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 521
NWS Storm Prediction Center Norman OK
305 PM CDT Fri Aug 19 2022
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central, southern, and eastern Iowa
Northern Missouri
* Effective this Friday afternoon and evening from 305 PM until
800 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Isolated damaging wind gusts to 65 mph possible
SUMMARY...Several discrete cells will pose a threat for mainly hail
up to golf ball size. These may consolidate into small clusters with
a threat for isolated damaging winds as well.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 45 miles south southwest
of Lamoni IA to 20 miles east northeast of Waterloo IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU1).
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.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
29025.
...Grams
SEL1
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 521
NWS Storm Prediction Center Norman OK
305 PM CDT Fri Aug 19 2022
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central, southern, and eastern Iowa
Northern Missouri
* Effective this Friday afternoon and evening from 305 PM until
800 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Isolated damaging wind gusts to 65 mph possible
SUMMARY...Several discrete cells will pose a threat for mainly hail
up to golf ball size. These may consolidate into small clusters with
a threat for isolated damaging winds as well.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 45 miles south southwest
of Lamoni IA to 20 miles east northeast of Waterloo IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU1).
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.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
29025.
...Grams
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW1
WW 521 SEVERE TSTM IA MO 192005Z - 200100Z
AXIS..60 STATUTE MILES EAST AND WEST OF LINE..
45SSW LWD/LAMONI IA/ - 20ENE ALO/WATERLOO IA/
..AVIATION COORDS.. 50NM E/W /49NNE MCI - 61WNW DBQ/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..55 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 29025.
LAT...LON 40009539 42659322 42659086 40009312
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU1.
Watch 521 Status Report Messages:
STATUS REPORT #2 ON WW 521
VALID 200000Z - 200140Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..JEWELL..08/19/22
ATTN...WFO...DMX...DVN...EAX...
&&
STATUS REPORT FOR WS 521
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC001-003-007-009-011-013-017-019-023-029-039-049-051-053-075-
077-087-095-099-101-103-107-113-117-121-123-125-127-135-153-157-
159-171-173-175-177-179-181-183-185-200140-
IA
. IOWA COUNTIES INCLUDED ARE
ADAIR ADAMS APPANOOSE
AUDUBON BENTON BLACK HAWK
BREMER BUCHANAN BUTLER
CASS CLARKE DALLAS
DAVIS DECATUR GRUNDY
GUTHRIE HENRY IOWA
JASPER JEFFERSON JOHNSON
KEOKUK LINN LUCAS
MADISON MAHASKA MARION
MARSHALL MONROE POLK
POWESHIEK RINGGOLD TAMA
TAYLOR UNION VAN BUREN
WAPELLO WARREN WASHINGTON
WAYNE
$$
MOC001-003-005-061-063-075-079-081-087-129-147-171-197-199-211-
227-200140-
MO
. MISSOURI COUNTIES INCLUDED ARE
ADAIR ANDREW ATCHISON
DAVIESS DEKALB GENTRY
GRUNDY HARRISON HOLT
MERCER NODAWAY PUTNAM
SCHUYLER SCOTLAND SULLIVAN
WORTH
$$
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.
$$
STATUS REPORT #1 ON WW 521
VALID 192145Z - 192240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..JEWELL..08/19/22
ATTN...WFO...DMX...DVN...EAX...
&&
STATUS REPORT FOR WS 521
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC001-003-007-009-011-013-017-019-023-029-039-049-051-053-075-
077-087-095-099-101-103-107-113-117-121-123-125-127-135-153-157-
159-171-173-175-177-179-181-183-185-192240-
IA
. IOWA COUNTIES INCLUDED ARE
ADAIR ADAMS APPANOOSE
AUDUBON BENTON BLACK HAWK
BREMER BUCHANAN BUTLER
CASS CLARKE DALLAS
DAVIS DECATUR GRUNDY
GUTHRIE HENRY IOWA
JASPER JEFFERSON JOHNSON
KEOKUK LINN LUCAS
MADISON MAHASKA MARION
MARSHALL MONROE POLK
POWESHIEK RINGGOLD TAMA
TAYLOR UNION VAN BUREN
WAPELLO WARREN WASHINGTON
WAYNE
$$
MOC001-003-005-061-063-075-079-081-087-129-147-171-197-199-211-
227-192240-
MO
. MISSOURI COUNTIES INCLUDED ARE
ADAIR ANDREW ATCHISON
DAVIESS DEKALB GENTRY
GRUNDY HARRISON HOLT
MERCER NODAWAY PUTNAM
SCHUYLER SCOTLAND SULLIVAN
WORTH
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (10%)
|
Probability of 1 or more strong (EF2-EF5) tornadoes
|
Low (5%)
|
Wind
Probability of 10 or more severe wind events
|
Low (20%)
|
Probability of 1 or more wind events > 65 knots
|
Low (20%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (40%)
|
Probability of 1 or more hailstones > 2 inches
|
Mod (30%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
Mod (60%)
|
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.
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