Ghostly AM Halloween fog, easing into November

Halloween 2013 opens with a ghostly gray fog blanket over Minnesota. Dense fog advisories, and visibility well under one quarter mile greet many Minnesotans this Halloween.

URGENT - WEATHER MESSAGE

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

1146 PM CDT WED OCT 30 2013

...WIDESPREAD DENSE FOG EXPECTED THROUGH THURSDAY MORNING...

DENSE FOG IS EXPECTED TO REMAIN IN PLACE FOR MUCH OF CENTRAL AND SOUTHERN MINNESOTA INTO WEST CENTRAL WISCONSIN OVERNIGHT. VISIBILITIES WILL BE REDUCED TO ONE QUARTER OR MILE OR LESS... WITH SOME LOCATIONS EXPERIENCING VISIBILITY NEAR ZERO. AREAS MOST SUSCEPTIBLE TO DENSE FOG INCLUDE THOSE ALONG AND EAST OF A LINE FROM ALEXANDRIA TO WILLMAR TO GAYLORD TO FARIBAULT. TRAVELERS ARE URGED TO USE EXTRA CAUTION BY REDUCING SPEED...USING LOW BEAM HEADLIGHTS AND ALLOWING EXTRA SPACE BETWEEN VEHICLES.

A DENSE FOG ADVISORY REMAINS IN EFFECT UNTIL 10 AM CDT THURSDAY.

* VISIBILITY: VISIBILITIES WILL BE REDUCED TO ONE QUARTER MILE OR LESS...INCLUDING NEAR ZERO...DUE TO WIDESPREAD DENSE FOG.

* IMPACTS: HAZARDOUS DRIVING CONDITIONS CAN BE EXPECTED DUE TO THE REDUCED VISIBILITIES. THIS INCLUDES INTERSTATES...EVEN WITHIN THE TWIN CITIES METRO REGION. IN ADDITION...WITH THE FOG LINGERING THROUGH DAYBREAK...MOTORISTS ARE URGED TO ALLOW EXTRA TIME FOR THE MORNING COMMUTE AND TO BE ON THE LOOKOUT FOR CHILDREN AND SCHOOL BUSES.

There's some good news on the weather maps if you don't want to shovel just yet. It looks like we may just ease into November this year.  No big scary Halloween storms lurk on the maps for 2013. I'm grateful for that.

The first few days of November don't exactly scream Indian Summer, but temperatures hovering around 50 degrees will give many of us a chance to get those last leaves up and get the boat and yard put to bed before the snow flies for real.

Meanwhile, East Coast residents are still recovering a year after Hurricane Sandy, and we are all still learning meteorological lessons from the superstorm.

The well publicized success of the European model over National Oceanic and Atmospheric Administration's forecast models with Sandy has lead to positive changes. The arms race to improve NOAA's forecast models is on. The Europeans are also upgrading computing capacity. And it turns out how we communicate approaching weather threats is critical to how well the public prepares. Some interesting perspective below in the blog today.

London Fog

What to be for Halloween this year? Sherlock Holmes would be a good choice if Halloween was Wednesday night and Thursday morning..

The northern end of this clammy weathermaker is ripe for thick fog into early Thursday. Temperatures and dew points are close, and light winds create the ideal environment for low clouds, drizzle and potentially thick fog. Here's the map with clouds and relative humidity levels approaching 100 percent at many reporting sites in Minnesota from  NOAA's Mesowest project.

Trick or Treatcast: Cloudy & cool

The bulk of the drizzle should slide east by trick or treat time, but the clouds will hang in most of eastern Minnesota. Trick-or-treat temperatures should hover in the mid-40s. Here's  the hourly breakdown of the Euro model data for Halloween 2013 from Weatherspark.

Fall Colors Fade

There have been (some) nice sunny days to soak in the fall colors this year. But I'd have to say overall that while the colors have been good, our weather has been better for leaf peeping in years past. Most of the state is now 'past peak' with some color clinging to the Twin Cities metro area and southeast Minnesota.

Here's the (last?) fall color map from the Minnesota Department of Natural Resources.

Norwegian town uses giant mirrors harvest winter sun

Minnesotans are all too familiar with the sun deprivation that this time of year can bring.  Here's a new way to beat the winter blahs?

The Norwegian town of Rjukan is getting creative when it comes to harnessing sunlight into the mountain shaded village. Giant mirror on the mountainside track the sun by computer and beam it into the town square. Desperate or ingenious? Possibly both? Do they sell tickets on sunny days to avoid overcrowding? Is there an application that can penetrate Minnesota's thick clouds? So many questions.

http://www.youtube.com/watch?v=fxf1cMNtYzM&feature=youtube_gdata

Sandy still delivering lesson 1 year later

There's been a lot of coverage on where we stand a year after Superstorm Sandy. The past year has exposed some major weaknesses in NOAA's numerical weather prediction capabilities, and shown us just how vulnerable our coastal areas are to hurricane driven storm surges.

Climate changes do not seem to be driving more hurricanes, but even small sea level rises make our coasts much more vulnerable to the storm surges that do come roaring ashore.

I had the pleasure to speak with University of Washington atmospheric scientist Cliff Mass earlier this year at the American Meteorological Society's annual conference in Austin, Texas. I respect his well-thought-out take on many weather related topics, and he has some illuminating perspective on two key lessons learned since Hurricane Sandy tore up the coast one year ago. Here's an excerpt.

Reality Check:  U.S. Weather Prediction is Good, But Not the Best

     For the first time, a "secret" among U.S. meteorologists became generally known to the general population:  although very good, U.S. numerical weather prediction is no longer the best in the world.   During the week and a half run up to the storm, it became obvious that the global forecasts of the European Center for Medium Range Weather Forecasting (ECMWF) were superior.  Several days before the U.S. global model (the GFS), the ECMWF forecast model accurately forecast the path and intensity of the storm:  a  triumph of the technology.  This superiority of the ECMWF was no fluke and in the subsequent months the media highlighted other cases where the U.S. model was inferior.   But there was a silver lining to this revelation:  the origins of the U.S. modeling problems were discussed, including the National Weather Service's inferior computers.  And the concerns of the American people and their representatives in Congress led to nearly 25 million dollars of the Sandy Supplement being dedicated to a new computer for weather prediction.   As the new head of the National Weather Service Louis Uccellini has stated on several occasions:  the implications of this powerful new computer (available in about a year) will be revolutionary.  

Miscommunication:  A Hurricane By Any Other Name Can Still Be Devastating

A major communication snafu occurred with Sandy.   As the storm approached the coast, it was losing its tropical characteristics and becoming more like a midlatitude storm (the fancy name for this isextratropical transition).   So right before landfall, the National Weather Service downgraded Sandy to apost-tropical cyclone and responsibility for forecasting it was handed off to local Weather Service forecast offices.  Hurricane watches and warnings were dropped, as one of the most dangerous storms of the century approached the Northeast coast.  Keep in mind that the storm was still as strong as a hurricane, with maximum winds of 85 mph. And Sandy was much larger than the typical hurricane.  The name change was terribly confusing to the media and many local authorities, some of which started to downplay the storm.  Big mistake.   The National Weather Service recognizes these problems in the post-storm review and has changed its strategy...next time the Hurricane Center will stay with such storms through landfall, and the warnings/watches will continue.