Severe threat fades, Midday storms cause spotty damage

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Morning and midday storms caused spotty wind damage and produced hail up to 2″ in diameter as they rolled through Minnesota. The highest winds and damage focused on areas west and north of the metro.

Street flooding was reported in Monticello and Cambridge. This image was shot by @seth_kaplan around midday.

Street flooding in Cambridge. Image: Seth Kaplan

As of midday Xcel Energy reported 24,720 customers without power due to the storms.

Image: Xcel Energy

The severe threat remains this afternoon for parts of Wisconsin and southeast Minnesota.

Here’s the latest Twin Cities radar to track the storms.

Here are the latest warnings from the Twin Cities NWS.

Our summer cameo is a brief one this week in Minnesota. The muggy air is back, and so is the rain and thunder. Here’s NOAA’s GFS model timing on rain chances, which may linger through afternoon in the metro and eastern Minnesota.

Image: NOAA GFS data via Weatherspark

With dew points near 70 today there will be plenty of fuel in the air for rain & storms…and some of the rain could be locally heavy with totals over 1″ in some areas.

Slight severe risk

There’s a slight risk a few of the storms could reach severe limits. But time of day, cloud cover and limited solar heating may keep the highest severe risk to the east into Wisconsin.

The National Oceanic and Atmospheric Administration’s Storm Prediction Center paints a slight risk of severe storms in the Upper Midwest. Basically the risk is east of a Duluth-Twin Cities-Des Moines, Iowa, line.

Image: NOAA SPC

The cool front has slowed, and that leaves a longer window for storms…and slower moving storms that may bring the potential for some locally heavy rainfall. Here’s a look at the wind shift and soggy 60s dew points in Minnesota.

Image” NOAA via College of Dupage

Warm front took its sweet time

The warm front that sailed into Minnesota Wednesday was an interesting one. Clouds hung tough for most of the day in the metro, but the clearing line pushed north late. Where the sun was out most of the day, temps soared into the 80s in south central and southwest Minnesota, and even into the 90s in South Dakota.

Check out NOAA’s 1 kilometer Geostationary Operational Environmental Satellites image from late Wednesday. I’ve overlaid temps and dew points, which soared in the warm sector behind the warm front.

Image: NOAA via College of Dupage

The result? A slightly busted forecast for the metro as clouds hung in most of the day, but a good one for the rest of southern and southwest Minnesota where the sun came out as scheduled.

Shine on harvest moon

We should see enough clearing the next few nights to enjoy the nearly full harvest moon over southern Minnesota. The harvest moon is defined as the full moon closest to the autumnal equinox, which happens this Sunday at 3:44 p.m central time.

Harvest moon rises over the Sonoran Desert in Arizona. (Image: NASA)

Here’s some great info on the harvest moon from EarthSky.

In traditional skylore, the Harvest Moon is the full moon closest to the autumnal equinox, and depending on the year, the Harvest Moon can come anywhere from two weeks before to two weeks after the autumnal equinox.

The Harvest Moon for 2013 falls on the night of September 18 or September 19, depending on your location on the globe. In North America, the crest of the moon’s full phase comes before sunrise September 19. at 11:13 UTC. That’s 6:13 a.m. central time in the U.S. on September 19, 2013. (Translate UTC to your time zone.)

So the night of September 18-19 has the brightest, fullest moon for the Americas. For us, by the night of September 19-20, the moon will be waning. On average, the moon rises about 50 minutes later each day.

But when a full moon happens close to the autumnal equinox, the moon (at mid-temperate latitudes) rises only about 30 to 35 minutes later daily for several days before and after the full Harvest moon. Why? The reason is that the ecliptic – or the moon’s orbital path – makes a narrow angle with the evening horizon around the time of the autumn equinox.

The narrow angle of the ecliptic results in a shorter-than-usual rising time between successive moonrises around the full Harvest Moon.

Watching for Jerry Hopefully Jerry won’t make an entrance like Kramer.

Conditions are still favorable for the formation of Tropical Storm Jerry in the next 48 hours. NOAA’s National Hurricane Center still gives a 70 percent chance that Jerry will develop in 48 hours.

(Image: NOAA/NHC)

Here’s the (all caps) discussion from the National Hurricane Center.

SATELLITE IMAGES AND SURFACE OBSERVATIONS FROM MEXICO INDICATE  THAT THE BROAD AREA OF LOW PRESSURE IS NOW CENTERED OVER THE GULF OF MEXICO WEST OF THE YUCATAN PENINSULA. THE ASSOCIATED SHOWER ACTIVITY IS CURRENTLY POORLY ORGANIZED…AND THE HURRICANE HUNTER MISSION SCHEDULED FOR THIS AFTERNOON HAS BEEN CANCELLED. THIS SYSTEM IS EXPECTED TO MOVE WEST-NORTHWESTWARD OVER THE SOUTHWESTERN GULF OF MEXICO DURING THE NEXT COUPLE OF DAYS…WHERE ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE CONDUCIVE FOR THE FORMATION OF A TROPICAL DEPRESSION. THIS SYSTEM HAS A HIGH CHANCE…70 PERCENT… OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AND A HIGH CHANCE…80 PERCENT…OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS. REGARDLESS OF DEVELOPMENT…THIS DISTURBANCE WILL LIKELY SPREAD HEAVY RAINS OVER PORTIONS OF EASTERN MEXICO AND COULD CAUSE LIFE-THREATENING FLOODS AND MUDSLIDES OVER AREAS ALREADY IMPACTED BY TORRENTIAL RAINS DURING THE PAST SEVERAL DAYS.

The suite of hurricane models are still widely divergent on solutions for track and intensity for Jerry. As we say in the weather biz, stay tuned.