Rain's In The Forecast After A Record Breaking Week
by Angela Schilling, Meteorologist
March 16, 2012 10:10 AM
To say this has been a record-breaking week would be an understatement. As of Friday morning we have already broken 3 records in Sioux Falls with high temperatures, and I think by this afternoon we'll be at four. The average temperature in South Dakota for the middle of March is around the lower to middle 40’s. March is also the snowiest month in Sioux Falls with an average of around 8 inches. We started off this record breaking week with a high of 72 degrees last Saturday and even topped 79 degrees in Sioux Falls on Tuesday. As we head into the upcoming weekend more records could be broken, not only for highs, but also for lows. Rain is in the forecast for the early portion of next week, mainly on Monday and Tuesday.
With an abnormally dry fall, winter, and now start to March, northwest, Iowa and southwest Minnesota are still in a severe drought, with very dry conditions extending west of the James.
This past week we also dealt with numerous Red Flag Warnings, where fire danger becomes more of an issue. Fire danger becomes a threat when you have very dry conditions, warm weather, and breezy winds, which sums up this past week in a nutshell. We’ll start things off with this past Tuesday where we hit 79 degrees in Sioux Falls, smashing our old record of 70. Almost everyone beat their old record for March 13th, with the exception of Marshall, SD and Yankton.
We could break several records on Friday as well, with abundant sunshine in place and a huge ridge of high pressure aloft. The image below shows the jet stream with warm air over the plains and colder air to our west over the Pacific Northwest. The second image below shows record highs for Friday the 16th as well as our forecasted highs.
As we head into this weekend a ridge will still be in place, keeping us warm and well above average. At the surface we’ll begin getting a southerly flow Friday evening, drawing in more moisture both tonight and tomorrow. Saturday could even be considered a little bit sticky with dew points close to 60 degrees. We’ll remain dry on Saturday with the potential for storms as we head into next week. The bulk of the activity will begin on Monday, but we could see a few isolated storms beginning Sunday afternoon. On Sunday an area of low pressure will be just off to our west into northeast Wyoming, out ahead it we will be in a very unstable air mass with temperatures in the upper 70’s and lower 80’s, combined with fairly high dew points for this time of year.
As the trough moves closer and closer our chances for thunderstorms greatly increases. Notice on the image above how the trough is well to our west on Sunday, but by Monday morning it will be knocking on our doorstep. Which means the threat for thunderstorms is not nearly as high as it is for Monday. If we do get a few thunderstorms to develop Sunday afternoon, they may form along a dry line, which separates dry air from moist humid air. The image below shows dew points, with high moisture east of the James and dryer conditions to the west, it is along that boundary where storms may fire up, that is if they do at all Sunday afternoon.
With a huge ridge of high pressure aloft, thunderstorms will be kept to a minimum until early next week. Without a strong forcing mechanism on Sunday the severe threat is quite low overall, however, the Storm Prediction Center has issued a slight risk from about Aberdeen southward, and then extending west to east from Pierre to Huron, South Dakota…with the main threats being large hail and strong winds. Make sure to stay tuned to KDLT and KDLT.com for the very latest.