Quantitative Precipitation Forecast Discussion NWS Weather Prediction Center College Park MD 256 PM EDT Wed May 23 2018 Prelim Day 1 QPF Discussion Valid May 24/0000 UTC thru May 25/0000 UTC Reference AWIPS Graphics under...Precip Accum - 24hr Day 1 ...Lower MS Valley---central Gulf coast into the Southeast/southern Mid-Atlantic,,, Widespread scattered diurnally enhanced convection likely day 1 along and to the south of the nearly stationary frontal boundary expected to lie from the Lower MS Valley---across the central Gulf coastal region and into the Southeast/southern Mid-Atlantic. With pw values expected to remain much above average along and south of this front---locally heavy precip totals possible---although confidence is low with details. One region of potential max precip will be in the vicinity of the nearly stationary surface to mid level circulation in the vicinity of central Georgia. Precip may focus near this center and then to the west southwest and northeast along the above mentioned frontal boundary position and/or surface trofs separate from the frontal boundary positions emanating from this nearly stationary low. ...Northern Rockies--- Northern Plains into the Upper MS Valley... Height falls pushing northward Wednesday across the Northern Rockies will move on a more east northeast track Thursday across the Northern Plains and toward the Upper MS Valley. The model consensus is for the well defined comma head/deformation precip area currently stretching from the Northern Rockies into the Northern High Plains to weaken at the beginning of the day 1 time period with more scattered precip near the primary height fall center over the Northern High Plains. At the same time---broadly difluent upper flow downstream of these height falls will support scattered convection from the Northern Plains into the Upper MS Valley. Areal average moderate precip totals depicted with locally heavier amounts likely where convection maximizes. ...Central to Southern High Plains... A lee trof/dry line will extend across a large area from the Central to Southern High Plains day 1. The broadly difluent upper flow expected across the Northern Plains/Upper MS Valley will also extend southward across the Central to Southern High Plains. This will support widespread scattered convection---primarily during the first 6 to 9 hours of the day 1 period tonight and then again late Thursday afternoon. Confidence in qpf details is low in this flow regime with a myriad of model solutions. The HREF mean was used to mitigate the model to model and model run to model run differences. Moderate areal average amounts depicted with locally heavier totals likely where convection maximizes. ...Northern California---portions of the Pacific Northwest---Northern Great Basin into the Northern Rockies... Widespread diurnally driven shower and thunderstorm activity likely early in the upcoming day 1 time period and again late in the period during Thursday afternoon. PW values expected to remain above average across these regions in the wake of the lead area of height fall ejecting north into the Northern Rockies early day 1 and ahead of the developing closed low off the California coast late day 1. Generally light to moderate totals expected across these areas--with isolated heavier totals possible. Oravec