Updraft: April 6, 2011 Archive

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Storm season is upon us

Posted at 6:45 AM on April 6, 2011 by Craig Edwards
Filed under: SKYWARN, Thunderstorms

We've had such a chilly start to spring it's hard to believe that the threat of severe storms is perhaps right around the corner. Are you mentally prepared for the wrath of thunderstorms.

Eye-balling the latest weather maps, there is some consistency in the models placing parts of central and southern Minnesota in a risk for frisky thunderstorms on Saturday afternoon and evening.

Click on SPC Severe Weather Outlook page here.

This is still a ways out, but the Storm Prediction Center is giving a heads up on the potential for strong storms in their experimental long range severe weather outlook. The red circle for day four is for Saturday. The day five circle is for Sunday's threat.

Today, the National Weather Service will conduct their weekly test of the NOAA Weather Radio All Hazard warning alert at 1pm. Do you know where your weather radio is? It's a good day to track it down and plug it back in for a test.

Main stream rivers continue to be at flood stage or higher in most parts of the state. Overnight, the Red River at Fargo rose above major flood stage of 30 feet. The forecast is still on track for a crest of 38 to 41 feet early next week in Fargo.

Track the Red River flood forecasts out ouf Grand Forks NWS.

Here's the latest outlook for liquid precipitation from NOAA for the weekend that was issued yesterday afternoon.

Is it any coincidence that the Twin Cities Metro Skywarn workshop is on Saturday in Minneapolis?

Still looking for an opportunity to become a Skywarn spotter. Here's a link to upcoming Skywarn trainiing sessions. Check with your local NWS office for other training sessions.

CE
naturesmessenger.com

Where the weather comes from

Posted at 4:07 PM on April 6, 2011 by Craig Edwards

Since we all live, work and play on the surface of the Earth. Thus we focus are forecast sensible weather at ground level. The real action in the weather world is racing around the planet in the jet stream. Here's the wind field and forecast heights of the 500 millibar level for midday on Saturday. Notice the maximum winds streaking across northern Minnesota a large swath of 80 to 90 mph winds in the southwest portion of the country.

Meteorologists are trained to monitor the model output at all levels in the vertical profile. Jet streams transports energy around the globe. There are both long wave weather patterns and embedded short waves or what we call troughs or ridges moving through the wind maximum fields. Troughs or low pressure are associated with precipitation. Rigdes or high pressure mean air settling and more tranquil.

For the weekend weather forecast we are monitoring the trend of the models with both the long wave and short wave pattern developing in the southwest corner of the Nation. The details on the timing of precipitation, intensity and specific location get sorted out in the dynamic transfer of heat and cold, along with moisture.

This is a long way to go to set up the conundrum the forecasters will have on the prediction of thunderstorms in Minnesota for the weekend. It looks like there will be a convective cluster of thunderstorms near southern Minnesota on Saturday evening. Follow along with Paul's Updraft blog the rest of the week to see how your weekend plans (perhaps a Twins game) may be impacted by the forces of the jet stream.

Here's a very busy map from NOAA on the hazards that are lurking for the next few days.