Old Res Weather
Lexington, Massachusetts, USA
34°F
11/30/2022 1:49am
- Overcast
-
34.0°F / 1.1°C
-
31.6°F
-
91%
- Calm, 10-min avg: Calm, gust: None
- 10 miles
- 0.00 in
- $VPuv None
National Short Range Forecast Discussion
Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 319 PM EST Tue Nov 29 2022 Valid 00Z Wed Nov 30 2022 - 00Z Fri Dec 02 2022 ...Heavy snow for the Cascades, Sierra and Northern Rockies... ...There are moderate flash flooding and severe weather threats over portions of the Lower Mississippi & Tennessee Valleys and Southeast tonight... An upper-level trough will move across the Midwest and Northeast over the next couple of days. An upper low will open into a trough and amplify while it enters the Northwest. A deep low pressure system currently moving through the Mississippi Valley will continue to focus showers and thunderstorms across the region and points eastward over the next couple of days. The most immediate threats will come from potential severe thunderstorms and excessive rainfall that are forecast for portions of the Lower Mississippi Valley, Southeast and central Gulf Coast tonight. A moderate risk of excessive rainfall leading to flash flooding is in effect over parts of southern Mississippi, southwestern Alabama and far western Florida embedded within a broader slight risk encompassing the Southern Appalachians, Lower Mississippi Valley and Southeast. Training thunderstorms may cause exceptionally heavy rain rates for the aforementioned areas. A moderate risk of severe thunderstorms is in effect over parts of northeastern Louisiana, extreme southeast Arkansas, central and northern Mississippi and northwest Alabama. Strong tornadoes, very large hail and severe wind gusts are forecast overnight. Regional outbreaks of severe thunderstorms and tornadoes are forecast for parts of the Lower Mississippi Valley tonight. Reduced visibility in the evening will add additional danger to those traveling within the affected areas tonight. Elsewhere, another low pressure system will bring heavy low elevation rain and heavy mountain snow to the Pacific Northwest tonight through Wednesday before shifting its attention to southern Oregon and northern/central California on Thursday. Anywhere between 1-2 feet are likely for the Cascades on Wednesday with isolated higher amounts possible. Parts of northern Washington/Idaho and central/southern Idaho may receive between 4-8 inches through tomorrow. Snowfall will pickup over the southern Cascades, northern California and the Sierra on Thursday with 1-2 feet of snow possible for these areas. An additional 8-12 inches of snow are possible for parts of the Northern Rockies on Thursday. Winter Storm Watches Warnings and Winter Weather Advisories are in effect over much of the Pacific Northwest and western mountain ranges. Some light to moderate snowfall is forecast to impact portions of the Upper Midwest/Great Lakes through tomorrow as moisture wraps around the low pressure system and interacts with a cold continental airmass flowing into the central third of the country. Winter Weather Advisories and Winter Storm Warnings are in effect from southern Minnesota to the western Upper Peninsula of Michigan. The departing cold front in the East will shift winds out of the northwest leading to the development of lake effect snow bands downwind of the Lower Great Lakes where 6-12 inches may fall on Thursday. Temperatures will be above average across the East Coast through Wednesday afternoon when the cold front will pass and drop temperatures. The Great Plains begin to warm up beneath upper high pressure on Thursday. Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php