Hello and happy Monday everyone hope all is well on this March 14th. We are less than a week away from the Vernal Equinox or the first day of spring and temperatures will reflect that as we slide through the week!
A modest warm up is expected this week with temperatures warming 10F to nearly 20F above normal by Wednesday, mainly east of the Rockies. Readings will remain mild through the week – let the thaw begin!
High Temperatures Wednesday
This is a quick look at what to expect temperature-wise Wednesday. Note the bubble of warmer weather stretching north along the Front Range of the Rockies into the Upper Midwest. Again, readings are expected to be a good 10F to 20F degrees above normal, but at this time of the year… the warmer weather means the potential for springtime flooding, which is looking likely for many in the Red River Valley, the Minnesota River Valley and the Mississippi River Valley of Minnesota and the eastern Dakotas, where sandbagging is in full force right now.
Key Factors Adding Up…
Local hydrology forecasters in the Upper Midwest haven’t seen flood indices this high for a while. A few factors are going into the major flood threat this spring.
1.) Heavy rainfall last fall kept the soil saturation high through the winter months. Since the soil is mostly frozen and mostly saturated, the expected snow melt is likely to be runoff into rivers, streams and other major tributaries contributing to the expected higher than normal water levels.
#2.) A deeper than normal snow pack across the potential flood zones with lots of water still locked in the snow pack. Surface observing stations are still reporting 6″ or more of snow on the ground with up to 2″ of water locked in the snow – YIKES!! The image below shows contoured model derived snow pack, with some of the latest snow depths reported by local surface observing stations.
#3.) A stretch of warm weather along with a heavier rain potential. The forecast this week in the locations listed above will likely see 40s and 50s through much of the week. We are also tracking a couple of chances of light rain/snow, but a much larger system is taking aim at the region by the upcoming weekend. The image below shows the ‘potential’ storm coming in for the weekend. This is not set in stone yet, but it shows the potential ‘heavier’ rain this weekend. The latest model runs show up to 1″ of liquid rain falling with this system in spots that do without the heavy rain.
#4.) Ice Jams. Rapid snow melt is never good for areas that are still (mainly) frozen. As ice breaks up along river, ice begins to coagulate in river bends, backing up water flow… this process in known as “ice jams” – which can further exacerbate flooding potential along river beds.
Current Weather Set Up
The weather today shows a slower moving storm over the middle Mississippi valley, kicking up snow, rain and strong storms across the region. Severe weather is possible later today across the orange shaded regions of the Lower Mississippi Valley later today into the evening hours. The main threat with this system will be large hail and damaging winds, but isolated tornadoes cannot be ruled out.
Precipitation Through Thursday
The Hydrological Prediction Center shows precipitation amounts through AM Thursday over 1″ in already waterlogged areas. Flood potential remains high in these areas as well. If you live in locations that are experiencing flooding issues, remember to never cross a water-covered road or wade into rapidly flowing waters, as you can be easily swept away. Note the large blob of moisture along the coast of the Pacific Northwest. The parade of powerful Pacific storms will continue to whip the coast with heavy rain and wind, which will transition into heavy snow in the high elevations.
Watches and Warnings
As expected, flood warnings continue for counties/parishes shaded in green for locations that have been hit hard with heavy rain over the last few weeks. Also, note the wintry headlines in Missouri on the colder, northwest side of the low tracking through the region. A slushy 3″ to 6″ of snow is possible in these areas through this Monday. The other areas highlighted in winter headlines includes the Pacific Northwest – as Pacific moisture lifts into the high elevations of the Olympics, up to 3ft. of snow is possible through PM Tuesday/AM Wednesday.
The 8 to 14 day temperature and precipitation outlook shows above normal temperatures where colors are orange/red and below normal temps where colors are blue. Above normal precipitation changes look to be setting up from the Southwest into the Great Lakes Region through the end of the month.
That’s all for now, thanks for tuning in on this Monday – have a good rest of the day and come back again tomorrow, won’ t you?!
Meteorologist Todd Nelson – WeatherNation LLC