Old Res Weather
Lexington, Massachusetts, USA
68°F
8/10/2022 3:45am
- Overcast
-
67.6°F / 19.8°C
-
63.3°F
-
86%
- Calm, 10-min avg: Calm, gust: 4 mph
- 10 miles
- 0.00 in
- $VPuv None
National Short Range Forecast Discussion
Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 410 PM EDT Tue Aug 09 2022 Valid 00Z Wed Aug 10 2022 - 00Z Fri Aug 12 2022 ...Hot weather to continue from the Northwest into the Plains, some relief by Wednesday for the Northeast... ...Heavy Rain and Flash Flooding threat from the Ohio Valley into the Central Appalachians... ...Monsoonal Showers to continue from the Southwest, portions of California and into the Great Basin... A key weather story over the Lower 48 today remains the prolific heat over the Interior Northwest and I-95 corridor in the Northeast, with modest relief from the record high temperatures anticipated this week. Over the Northwest, the heat streak is forecast to moderate some over the next several days, although notable above average temperatures will linger over the Interior Northwest before spilling into the Plains by midweek. This will translate to daily high temperatures to the mid-upper 90's over parts of the Interior Northwest and east across the Plains. Heat advisories and Excessive Heat Warnings are in effect across eastern Washington, Oregon and northern Idaho through the afternoon. Moreover, the warm weather and gusty winds will support an Elevated fire weather risk tomorrow across portions of the Interior Northwest, per the Storm Prediction Center. Meanwhile, cooler temperatures will begin to filter into the Great Lakes and Northeast today and continue through Wednesday as a slow moving cold front meanders south across the Interior Northeast into the Upper Mississippi Valley. Much of the East will have another day of the heat before temperatures start to moderate to around average, before a secondary cold front in Canada brings a reinforcing shot of cool air into the region by the end of the work week. Temperatures aside, showers and thunderstorms developing ahead of and along the slow moving lead cold front will bring a threat of heavy rainfall and flash flooding from the Mississippi Valley to the Central Appalachians; these locations have been very wet the last few weeks, so it would not take much rain to cause flash flooding. As such, WPC maintains a Slight Risk (level 2/4) of Excessive Rainfall across the Mississippi Valley into the Central Appalachians through Thursday. The Western half of the CONUS remains wet, too. A stagnant area of upper high pressure will build across the Rockies, in turn pushing deep layered moisture northward. This above average moisture will help trigger widespread scattered monsoonal showers and thunderstorms across these areas over the next few days. Isolated flash flooding is possible across these areas, especially over burn scars, slot canyons, dry river beds or urban areas. The Southeast quarter of the Lower 48 will also hold in a stagnant, wet pattern. The frontal boundary pressing into the Ohio Valley and Northeast will not make much headway south through this week, keeping the Southeast in the warm sector through Thursday. As such, expect widespread showers and thunderstorms in the region, where portions of the Lower Mississippi Valley and Central Gulf Coast have the best chances for heavy rains. The clouds and rain across this area will also keep high temperatures over the next few days slightly below average. Asherman/Campbell Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php