Quantitative Precipitation Forecast
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FOUS30 KWBC 150754

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
353 AM EDT Thu Mar 15 2018

VALID 12Z Thu Mar 15 2018 - 12Z Fri Mar 16 2018

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

...Northern California...

Here we removed a small Marginal Risk area inherited from the old
Day 2 period. The only real factors arguing toward heavy downpours
and any hydrologic response would be the steep lapse rate
environment / convective enhancement and recent wet weather. As a
measure of the overall wetness of the hydrologic system in coastal
northwest California, however, the rivers are well below action
stage. This, and the precipitable water values peak only just
above a half inch today, and showers will be moving along at a
15-20 knot clip. With snow levels as low as 2000 feet as well, the
event does not seem to warrant Marginal Risk probabilities for
excessive rainfall.



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