Postcard perfect now, watching Erika

It doesn't get any better than this. Bright sun. A deep blue late summer sky. A blissfully mild dry air mass. Weather Lab sunflowers towering overhead.

These are the days we savor in Minnesota. Lazy high pressure drifts overhead through Wednesday. Thursday starts sunny and warm, the next front sparks a few scattered showers and thunderstorms by Thursday night.

The maps please.

Southerly flow returns Wednesday as a milder air mass eases into Minnesota. "Top 10" weather day? You can make the case Wednesday as the best weather day of the year across Minnesota. In what is measurably one of the best summers on record, that's saying a lot.

The opening run of the Minnesota State Fair looks good overall. Thursday starts nice, Thursday night's shower chances linger into a cooler Friday. The first weekend of the Fair looks fantastic.

Keep in mind that the longer range 16-day GFS forecast can be like a desert mirage. The shimmering lake you see in the distance keeps showing up ahead, but never moves any closer.

Still the model has been consistent about suggesting a warmer and more humid pattern by the middle of next week. A shot at 90 or better during the second half of the fair's run? Why not?

Mysterious 'red dust' in Brown County

We get these into the Weather Lab every now and again. Many like this one are hard to diagnose. Thanks to Brown County Planning & Zoning's John Knisley for the heads up on some mysterious "red dust" settling on cars in southwest Minnesota.

Hey Paul, we have had a couple people call in to our office today concerned about a "Red Dust" on their vehicles - they were concerned about spray drift, but I was wondering if the smoke from the fires out west were carrying any particles with them that could have been red?  Pollen counts up?

John Knisley

Brown County Planning & Zoning

Water Planner, WCA Admin., Recycling Coordinator

Thanks for the heads up John!

These are always tough to diagnose. A fine wildfire smoke ash from western fires is always a possibility. But smoke has been pretty scarce across Minnesota today, though that is about to change as the next wave of smoke drifts east from the Dakotas tonight.

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One idea: Could it be (Red River Valley?) dust that was kicked airborne from high winds the past couple of days and settled out today?

My best guess!

Paul

Watching Erika

Tropical Storm Erika cycled today. A down mode, followed by some signs of up-cycling. She continues to chug steadily westward toward the Islands.

The models will twist and turn the next few days over the eventual track and intensity of Tropical Storm Erika. For now, NOAA's National Hurricane Center still favors Hurricane Erika in the Bahamas by Sunday. South Florida is now in the five-day track probability cone.

The bulk of the spread in model tracks favors a path just east of the Florida coast. But it's way too early, and too close to call that yet.

Here's more on the uncertainty behind the forecast from NHC.

TROPICAL STORM ERIKA DISCUSSION NUMBER 4

NWS NATIONAL HURRICANE CENTER MIAMI FL AL052015

500 PM AST TUE AUG 25 2015

After becoming quite disorganized in appearance earlier today,

Erika has made a bit of a comeback with increased deep convection

near and to the south of the center. Data from the Air Force

Hurricane Hunters indicate that the intensity is near 35 kt and

this is consistent with Dvorak estimates from both TAFB and SAB.

Erika has limited upper-level outflow over the northern semicircle

of the circulation, and microwave data suggest that the cyclone has

been ingesting some dry mid-level air. As in the previous

forecast, there is considerable uncertainty as to the future

intensity of this tropical cyclone. The SHIPS guidance indicates

increasing west-northwesterly shear over the next few days, and the

GFS and ECMWF global models do not strengthen the system during the

forecast period. The HWRF and GFDL models do show strengthening,

however, but along a track to the right of most of the guidance.

The official intensity forecast has been reduced a bit from the

previous one and is close to the model consensus.

A center fix from the aircraft indicates that the motion continues

to be near 280/17. A mid-level subtropical ridge to the north of

Erika should steer the system on a west-northwestward track for the

next several days. Late in the forecast period, there is

significant spread in the models, with those models that depict a

weaker system being farther south and west and those having a

stronger cyclone farther to the north and east. The official track

forecast has been adjusted a little to the left of the previous one

and is in line with the latest dynamical model consensus.

Stay tuned.