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FXUS01 KWBC 212018

PMDSPD



Short Range Forecast Discussion

NWS Weather Prediction Center College Park MD

417 PM EDT Tue May 21 2024



Valid 00Z Wed May 22 2024 - 00Z Fri May 24 2024



...There is a Moderate Risk of severe thunderstorms over parts of

the Middle Mississippi Valley on Tuesday and the Southern Plains/

Lower Mississippi Valley on Wednesday...



...There is a Slight Risk of excessive rainfall over parts of the

Upper/Middle Mississippi Valley and Upper Great Lakes on Tuesday

and Southern Plains/Lower Mississippi Valley on Wednesday and

Thursday...



...Heavy snow over the higher elevations of the Northern Rockies

and Northern Intermountain Region on Tuesday evening and Wednesday

evening...



On Tuesday evening, a front extending from the Upper/Middle

Mississippi Valley to the Southern High Plains will move eastward

to the Northeast Coast by Thursday evening. The southern half of

the boundary moves northward as a warm front over the Southern

Plains on Thursday, then dissipates by Thursday evening.



The front will fire showers and severe thunderstorms over Iowa,

southwest Wisconsin, northern Missouri, and northwestern Illinois.

 Therefore, the SPC has issued a Moderate Risk (level 4/5) of

severe thunderstorms over parts of the Middle Mississippi Valley

and a small part of the Upper Mississippi Valley through Wednesday

morning.  The potential hazards associated with these

thunderstorms are frequent lightning, severe thunderstorm wind

gusts, hail, and a few tornadoes. There will be the added threat

of EF2- EF5 tornados and severe thunderstorm wind gusts of 65

knots or greater over the region. Moreover, there will be an

additional threat of hail two inches or greater over parts of the

Mississippi Valley and the Central/Southern Plains.



Furthermore, the showers and thunderstorms will cause heavy rain

to develop over parts of Minnesota, western Wisconsin, northern

Iowa, and adjacent areas. Therefore, the WPC has issued a Slight

Risk (level 2/4) of excessive rainfall over the Upper Mississippi

Valley and Upper Great Lakes through Wednesday morning.  The

associated heavy rain will create mainly localized areas of flash

flooding, with urban areas, roads, small streams, and low-lying

areas the most vulnerable. Additionally, showers and severe

thunderstorms will develop southward over parts of the Southern

Plains. Moreover, showers and thunderstorms will develop over

parts of the Central Plains and Middle Mississippi Valley. 



On Wednesday, as the front moves southward and eastward over the

Southern Plains, the system will produce showers and severe

thunderstorms over parts of the Southern Plains and Lower

Mississippi Valley. Therefore, the SPC has issued an Enhanced Risk

(level 3/5) of severe thunderstorms over parts of the area from

Wednesday into Thursday morning.  The hazards associated with

these thunderstorms are frequent lightning, severe thunderstorm

wind gusts, hail, and a few tornadoes. In addition, there will be

an added threat of hail two inches or greater over parts of the

region.



Moreover, some of the showers and thunderstorms will produce heavy

rain over parts of the Southern Plains and Lower Mississippi

Valley. Therefore, the WPC has issued a Slight Risk (level 2/4) of

excessive rainfall over the Lower Mississippi Valley and Southern

Plains from Wednesday into Thursday morning.  The associated heavy

rain will create mainly localized areas of flash flooding, with

urban areas, roads, small streams, and low-lying areas the most

vulnerable.



On Thursday, the threat of severe thunderstorms decreases slightly

as the boundary moves northward over the Southern Plains/Lower

Mississippi Valley.  Therefore, the SPC has issued a Slight Risk

(level 2/5) of severe thunderstorms over the Central/Southern

Plains and the Lower Mississippi Valley on Thursday morning.  The

hazards associated with these thunderstorms are frequent

lightning, severe thunderstorm wind gusts, hail, and a few

tornadoes.



Similarly, the showers and thunderstorms will produce heavy rain

over parts of the Southern Plains/Lower Mississippi Valley.

Therefore, the WPC has issued a Slight Risk (level 2/4) of

excessive rainfall over the Lower Mississippi Valley and Southern

Plains on Thursday.  The associated heavy rain will create mainly

localized areas of flash flooding, with urban areas, roads, small

streams, and low-lying areas the most vulnerable.



Meanwhile, another front will move over the Pacific Northwest

overnight Tuesday, advancing to Upper Mississippi Valley and then

to the Southwest by Thursday evening. The system will produce rain

over parts of the Pacific Northwest overnight Tuesday. As the

boundary moves farther inland, the snow levels will lower,

producing snow at higher elevations over the Northwest. Overnight

Wednesday, the rain and higher-elevation snow will move into the

Northern Intermountain Region, producing heavy snow at the higher

elevations. On Thursday, the rain and higher-elevation snow will

move into the Northern Rockies. The system will create areas of

heavy snow over the highest elevations.





Ziegenfelder





Graphics available at

https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php



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