FOUS11 KWBC 051838

QPFHSD



Probabilistic Heavy Snow and Icing Discussion

NWS Weather Prediction Center College Park MD

238 PM EDT Tue May 5 2026



Valid 00Z Wed May 06 2026 - 00Z Sat May 09 2026



...Central Rockies and High Plains... 

Day 1...



...Significant late season snowstorm continues for the Rockies and

Denver Metro through Wednesday evening...



A secondary cold front initially near the WY/CO border will bank 

up against the lee side of the Front Range as it presses southward 

through the CO High Plains tonight into Wednesday. In the wake of 

the front, strengthening low-level upslope east to northeasterly 

flow combined with favorable jet dynamics aloft will support 

intensifying precip across the CO Rockies, the Denver Metro, and 

the I-25 corridor this evening into the overnight hours. Marginal 

surface temperatures early on may result in pockets of mixed rain 

and snow along with heavier bursts of all snow dependent on precip 

rate; however, post-frontal cold advection will drop temperatures 

near to below freezing area wide by Wednesday morning, changing any

lingering rain/snow to all snow as snow levels crash to between 

4500 and 5000ft. Moderate to heavy snow continues through Wednesday

morning from Cheyenne to Denver through the Front Range as forcing

for ascent maximizes within a fairly deep DGZ. Forcing sags 

southward Wednesday afternoon, shifting the focus for moderate to 

heavy snow to the Sangre De Cristos and San Juans as snowfall rates

gradually diminish north of the Palmer Divide. Snow mostly 

diminishes area wide by Wednesday evening with only a few lingering

showers across the Rockies of southern CO and northern NM into 

Wednesday night.



The latest Day 1 WPC probabilities of additional snowfall >4" are 

50-80% from Cheyenne southward to the Denver Metro and the Palmer 

Divide eastward to I-70 just west of Flagler. Probabilities of >8" 

are 50-90% from the Front Range and central Continental Divide 

mountains southward to the San Juans and Sangre De Cristos. 

Finally, probabilities of >12" are 60-90% for the high higher 

elevations of the Front Range including Rocky Mountain NP.



This late season winter storm continues to bring much needed 

precipitation to the Central Rockies and High Plains, providing 

some relief to places facing severe to extreme drought. With that 

being said, the moisture does not come without notable impacts. The

latest WSSI continues to highlight widespread Moderate impacts for

the I-25 corridor from Cheyenne through Denver and the Palmer 

Divide and Major impacts for the Front Range including Rocky 

Mountain NP. The heavy and wet nature of the snow on trees fully 

leafed out/in bloom and on power lines could result in tree damage 

and power outages. Snow-covered and icy roads will also become a 

greater concern as temperatures cool, leading to increasingly 

difficult travel (especially over higher mountain passes) overnight

into Wednesday morning's commute.





The probability of significant icing across the CONUS is less than

10 percent. 





Miller





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