Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
412 PM EDT Sat Jun 7 2025
Day 3
Valid 12Z Mon Jun 09 2025 - 12Z Tue Jun 10 2025

...THERE IS A MARGINAL OF EXCESSIVE RAINFALL ACROSS A LARGE PORTION
OF THE SOUTHERN AND EASTERN UNITED STATES...

Very few changes were made to the existing Marginal Risk, which
encompassed a broad area in the southern and eastern United States
along and ahead of a slowly advancing cold front. The air mass
ahead of the front will be characterized by above normal PWs and
widespread moderate to strong instability. Therefore, a day with
abundant areas of active convection containing relatively high
rain rates is expected. Confidence is not very high at this time in
the detail, particularly where concentrated areas of heavy rainfall
and/or localized extreme events may occur. However, based on
today's model guidance, this seems most likely in the following
locations, where a Slight Risk upgrade may eventually be needed:

1. Eastern Great Lakes and Central Appalachians. Instability is
projected to be more limited in these areas, but recent rainfall
may lead to wet conditions in advance, and there is better model
consensus on areas of over 1 inch QPF.

2. The Gulf Coast. A combination of strong instability and high PWs
would support organized convection and high rain rates, but there
is less model agreement on placement.

3. West Texas into Northeast New Mexico. PWs will be increasing and
quite anomalous (over the 90th percentile) along with fairly strong
instability. These areas will be removed from stronger mid-upper
level flow, likely leading to overall slower storm motions.

Lamers
Day 3 threat area: www.wpc.ncep.noaa.gov/qpf/99epoints.txt