Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
353 AM EDT Sun Oct 02 2022
 
Day 1
Valid 12Z Sun Oct 02 2022 - 12Z Mon Oct 03 2022 

...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS PORTIONS 
OF SOUTHERN UTAH AND SOUTHWESTERN COLORADO...

...Four Corners Region... 

An upper-level trough will be slowly tracking across the West 
while multiple shortwaves traverse the base of the trough. These 
impulses along with sufficient forcing, diurnal heating and PW 
values upwards of 2 inches will support and maintain showers and 
thunderstorms across much of the Four Corners region and into 
western Colorado and southern Wyoming. Some of the CAMs are 
showing rainfall rates around 0.50+ inch/hr, particularly over 
central/southern Utah and into Colorado and with areal averages of 
1+ inches as well. The Slight Risk that was already in effect to 
encompass vulnerable terrain of southern Utah into far 
southwestern Colorado was expanded farther to the west and 
southwest across southern Utah to reflect the latest QPF trends.

...Mid-Atlantic...

A frontal system will continue to track east from the Mid-Atlantic 
region during this period; however it will continue to be a focus 
for lingering showers and thunderstorms over this region, with 
higher amounts possible across portions of Virginia, Maryland, New 
Jersey, and Delaware. The QPF gradient is expected to sharpen as 
high pressure settles into the Northeast and allows a steady 
easterly flow.   Some the 12Z guidance members show heavy amounts 
developing along this axis of strong onshore flow and ascent but 
there is also a fair amount of model spread to lower the 
confidence with regard to if and where this swath of heavy rain 
may occur. The Marginal Risk area was maintained with minimal 
adjustments to reflect the latest WPC forecast.

Campbell
 
Day 1 threat area: www.wpc.ncep.noaa.gov/qpf/94epoints.txt