Free AC: Cool front brings delightful air mass; Tropical Storm “Chantal” triggers Hurricane Watch

Free AC Ahead:

Time to throw open the windows and give the AC a rest?

A cool front sweeping through Minnesota is delivering a fresh transfusion of Canadian air. Dew points hovered around the topical 70F mark early Tuesday.  Now an air mass more atypical for labor Day weekend sweeps in with dew points falling through the 50s by Wednesday.

The first real rain in 9 days swept through Minnesota Tuesday. Good timing…it was getting just a little dry around the edges, and the forecast looks dry until the weekend.

Enjoy the delightful respite. heat and humidity return for the weekend, and there are signs of at least a couple more 90+ days in store next week.

My lawn is happy with the AM soaking.

Rainy start Tuesday. Image: patrangelo77 PJ

A welcome shot of rain:

Tuesday AM rush hour was anything but for a few minutes as heavy T-Storms pounded the metro and most of Minnesota. Numerous reports tell of cars pulling over on the side of freeways in downpours too heavy to drive in. Street lights flashed on  in the storm darkened AM skies around 8-9am.

Several automated rainfall reports early on tallied over 2″, but it appears a glitch in the NWS data may have erroneously boosted totals.

MPX: 2 WSW Apple Valley [Dakota Co, MN] mesonet reports HEAVY RAIN of M2.60 INCH at 08:08 AM CDT – one hour.

Later storm reports indicate the potential problem with the “1 hour tabulation method.”

MPX: 2 WSW Apple Valley [Dakota Co, MN] mesonet reports HEAVY RAIN of U0.00 INCH at 08:08 AM CDTone hour precipitation tabulation method in question.

The Weather Lab in the west metro picked up .57″ rainfall as the storms rolled through this morning. That fits with other rain reports around the metro.

Huttner Weather Lab in west metro .57″

Eden Prairie .58″

Crystal Airport .44″

MSP Airport .34″

St. Paul Airport .72″

Here’s a look at the NWS/Wxunderground storm total rainfall from Tuesday morning. Note the patches of 1″+ rainfall mainly west of the metro.

Image: Wxunderground

Delightful air mass

It doesn’t get any better than this in July.

The tropical gunk has been pushed out by a freshening Canadian breeze.

Here’s the GOES 1km visible satellite shot from Tuesday PM with winds and dew points overlaid. Note the surface low spinning into Wisconsin…and a fresh northwest breeze pumping in dew points in the 50s in northwest Minnesota.

Image: NOAA data via College of Dupage

Check out the dew point plunge in Fargo from nearly 70F to 60F…and headed for the 50s.

Image: Red River Valley NWS

Best Weather in the Nation?

The new air mass sets Minnesota up for one of the finest runs of weather in the nation. Here’s the metro forecast the rest of the week. Tee time anyone?

Image: Twin Cities NWS

Tropical Storm Chantal: Bucking stiff headwinds

Chantal is chugging into the Caribbean…and fighting some unfavorable headwinds.

Image: NOAA

Still the storm may be able to reach hurricane strength in the next few days. Here’s the discussion from NOAA’s national Hurricane Center. (NHC)

AT 500 PM AST…2100 UTC…THE CENTER OF TROPICAL STORM CHANTAL WAS LOCATED NEAR LATITUDE 15.2 NORTH…LONGITUDE 63.7 WEST. CHANTAL IS MOVING TOWARD THE WEST-NORTHWEST NEAR 26 MPH…43 KM/H. THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT COUPLE OF DAYS WITH A GRADUAL DECREASE IN THE FORWARD SPEED.

ON THE FORECAST TRACK…THE CENTER OF CHANTAL WILL CONTINUE TO MOVE AWAY FROM THE LESSER ANTILLES TONIGHT…AND IS EXPECTED TO BE NEAR OR OVER THE DOMINICAN REPUBLIC BY WEDNESDAY AFTERNOON. CHANTAL IS EXPECTED TO BE OVER THE SOUTHEASTERN AND CENTRAL BAHAMAS ON THURSDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 65 MPH…100 KM/H…WITH HIGHER GUSTS. THESE WINDS ARE CONFINED TO A SMALL AREA TO THE EAST THE CENTER. CHANTAL IS EXPECTED TO BE NEAR HURRICANE STRENGTH BEFORE REACHING HISPANIOLA.

The “spaghetti plots” of various models track Chantal toward the southeast USA coastline this weekend.

Image: NOAA via SFWMD

The official NHC track brings Chatal to near the Carolina Coast by Sunday.

Image: NOAA NHC

Overall conditions featuring “wind shear” in the Atlantic do not look favorable for rapid intensification for Chantal in the next few days. But if the environment improves, Chantal may become a threat to the southeast USA Sunday or Monday. Remember, hurricane track forecast are far more reliable than intensity forecast…which show much less skill overall.

All eyes on Chatal the next few days in the southeast USA.

Paul Huttner