Quantitative Precipitation Forecast Discussion
NWS Weather Prediction Center College Park MD
252 PM EDT Wed Apr 04 2018


Prelim Day 1 QPF Discussion
Valid Apr 05/0000 UTC thru Apr 06/0000 UTC
Reference AWIPS Graphics under...Precip Accum - 24hr


Day 1

...Pacific Northwest into the northern Rockies...

Warm front will bring light rain/snow to Washington overnight
before a much more impressive surge of moisture pushes into
coastal Oregon/Washington by Thursday morning ahead of a cold
front. Precipitable water values of 0.75-1.00" (+2 to +2.5
standard deviations) will support widespread light to modest
amounts, generally 0.25" to 0.50" but a bit lighter in the valleys
and about 2-3 times that in the Olympics/Cascades. 110kt jet
streak should push into southwestern Oregon late Thursday morning
coinciding with larger PW anomalies (southward to NorCal) of about
+2 to +3 standard deviations. HREF mean (or blended means)
provided a good starting point for the Pac Northwest. Over
northern ID into MT/WY, also followed the 12Z HREF mean which
expanded the precip eastward along rising PW values, a ~120kt jet
out of SW Canada, and the surface front along/east of the Divide
with modest upslope potential on Thursday.


...Florida...

Cold front will push into south Florida early Thursday with
isolated showers and embedded convection. Hi-res models target
extreme southern portion of the peninsula tomorrow afternoon along
a convergence zone between northeast winds behind the front
(sinking into the Florida Straits) and sea breeze development.
Isolated local maxima may be .5-1" with healthier convection.


Fracasso