Instant spring at Target Field; flood threat; Japan fallout

Let's start with the good news!

Here's a lighter note in a world of troubling news to start your Tuesday.

Spring began at Target Field Monday!

I had a chance to chat with Minnesota Twins Head Groundkeeper Larry DiVito at Monday evening's AMS meeting in the Champion's Club at Target Field. Larry and his crew peeled off the agricultural fabric used to cover the turf at TF Monday.

"Winter began November 13th, and it ended today" said DiVito.

Larry has had the underground heaters turned on all winter long at TF. With the heaters set in the upper 30s and the tarp and snow cover on top of the field, the turf never really froze this winter at TF. These days, Larry cranks up the heaters to a comfy 52 degrees about 10" under the turf.

Larry and his crew are working this week to get Target Field turf ready for baseball. Now there's a sure sign of spring in Minnesota!

Edwards dazzles AMS meeting:

My partner in weather crime, MPR & Twins Meteorologist Craig Edwards put on a good show Monday night at the AMS Twin Cities Chapter meeting. Craig eloquently described the first season of providing weather support at Target Field, including some close calls and highlights. I had the pleasure of giving last months' AMS talk about weather coverage at MPR, and this was Craig's turn.

Edwards works the crowd in the Champion's Club at Target Field.

Fortunately the Twins lead charmed weather lives in 2010, seeming to dodge nearly every storm with only 2 games significantly affected by rain. Let's hope the good luck continues for fans in 2011! My weather "spidey senses" tell me the "law of weather averages" will make Craig a busier weather beaver at Target Field in 2011.

Gratuitous Target Field factoid:

Did you know there are 4.5 miles of "beer pipe" running through Target Field to pump beer to the concessions stands? I didn't either, until last night. I happened to snap a picture of the lines running high above the interior walkway heading the Target Field Weather Lab. (FYI, this was a "dry" AMS meeting.)

Talk about underground "utilities." Anyone besides me thirsty?

"Beer pipe" running under Target Field.

Warming trend kicks into high gear:

You'll really start to notice it's feeling more like spring today and the rest of this week. Southerly winds will prevail most of this week and into next week. With the exception of a minor speed bump on Friday, it looks like we will see a string of days in the 40s and 50s over the next week.

Warm week ahead. (Click to enlarge)

It looks like temperatures in much of Minnesota have a shot at 50 Wednesday, Thursday and again over the weekend into early next week. Temps will be running about 10 to 15 degrees above average this week. 50 is the average high in the metro for April 3rd!

Milder nights too!

One feature of this warm up is that temperatures may stay at or above freezing starting early Wednesday and lasting right into next week in much of Minnesota!

Rapid snow melt:

The string of days in the 40s and 50s and above freezing nights mean the pace of snow melt is going to increase rapidly this week. Several inches of snow will melt in the next week, and many locations could be down to dirty piles of snow by Sunday.

One thing to remember is that the snow that's left is nearly "glaciated" in many spots. That is to say, a winter's worth of water and ice is compresses and still locked up in the bottom few inches of the snow. That makes the last few inches the toughest to melt. (Kind of like losing those last few pounds?)

Flood threat grows:

As the snow melts, water will increase runoff into area rivers and streams this week. The hydrologists at the NCRFC recognize this, and they are in the process of running new models to gauge the increasing flood threat this week.

There is still a good 4" to 6"+ snow water equivalent (SWE) in the snow in the Minnesota River watershed.

4" to 6"+ snow water content in Minnesota River watershed.

Here's the latest flood outlook from NWS.

HYDROLOGIC OUTLOOK

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

452 PM CDT MON MAR 14 2011

...WARM TEMPERATURES THIS WEEK ARE EXPECTED TO INCREASE MELTING

AND POTENTIALLY LEAD TO RIVER FLOODING AS EARLY AS THIS WEEKEND AND

INTO EARLY NEXT WEEK...

A CHANGE IN THE WEATHER PATTERN WILL BRING WARMER TEMPERATURES TO

CENTRAL AND SOUTHERN MINNESOTA AS WELL AS WEST CENTRAL WISCONSIN

TOMORROW AND ESPECIALLY INTO WEDNESDAY AND THURSDAY. TEMPERATURES TOMORROW WILL BE IN THE LOWER 40S IN CENTRAL AND SOUTHERN MINNESOTA AND MID 40S IN WEST CENTRAL WISCONSIN. TEMPERATURES ON WEDNESDAY WILL WARM INTO THE UPPER 40S AND LOWER 50S. ON THURSDAY TEMPERATURES WILL RANGE FROM THE LOWER 40S IN WEST CENTRAL AND CENTRAL MINNESOTA TO AROUND 50 DEGREES ACROSS THE REMAINDER OF THE AREA. HIGHS ON FRIDAY WILL BE COOLER...BUT STILL IN THE MID 30S IN WEST CENTRAL MINNESOTA TO THE MID AND UPPER 40S IN SOUTH CENTRAL MINNESOTA AND INTO WEST CENTRAL WISCONSIN.

LOWS WEDNESDAY MORNING WILL DROP INTO THE MID TO UPPER 20S WHICH

WILL HELP SLOW THE MELTING PROCESS FROM TUESDAY. BUT FOR OVERNIGHT

WEDNESDAY NIGHT AND INTO THURSDAY MORNING...TEMPERATURES ARE NOT

EXPECTED TO DROP BELOW FREEZING ACROSS THE ENTIRE AREA WITH WITH

SOUTH CENTRAL AND EAST CENTRAL MINNESOTA ONLY FALLING INTO THE UPPER

30S TO NEAR 40 DEGREES. LOWS FRIDAY MORNING WILL RANGE FROM THE

MID 20S IN CENTRAL MINNESOTA TO THE LOWER AND MID 30S IN SOUTH

CENTRAL MINNESOTA AND WEST CENTRAL WISCONSIN. THE MELTING PROCESS

WILL CONTINUE FROM WEDNESDAY THROUGH THURSDAY NIGHT ALLOWING FOR

ROUGHLY 36 HOURS OF CONTINUOUS MELTING.

WE ARE ALSO LOOKING AT A COUPLE OF CHANCES OF RAIN IN THE NEXT 7

TO 10 DAYS. THE FIRST CHANCE WILL BE ON TUESDAY. AT THIS

TIME...PRECIPITATION AMOUNTS WILL BE LIGHT....A TENTH OF AN INCH

AND LESS. ANOTHER SYSTEM WILL MOVE ACROSS THE AREA ON THURSDAY. AS

WITH THE TUESDAY SYSTEM PRECIPITATION AMOUNTS ALSO LOOK LIGHT.

THE WEATHER PATTERN WILL REMAIN ACTIVE FOR NEXT MONDAY INTO

TUESDAY WITH POTENTIAL RAIN CHANCES. THESE SYSTEMS MAY BE ABLE TO

TAP INTO THE GULF OF MEXICO AND BRING AN INCREASED THE POTENTIAL

OF RAIN. THIS ACTIVITY IS STILL AT LEAST 7 DAYS OUT IN THE

FORECAST. SO PATTERNS MAY CHANGE. BUT IT IS WORTH WATCHING THIS

SYSTEM.

THE WARMING TEMPERATURES WILL BEGIN MELTING THE SNOW. AT THIS

POINT...RISES ARE EXPECTED IN THE MAIN STEM RIVERS THE LATER PART

OF THIS WEEK. HOW WARM WE ACTUALLY GET DURING THE DAY...AND HOW

WARM WE REMAIN OVERNIGHT AS WELL AS THE HUMIDITY LEVELS AND

WINDS...WILL BE THE MAIN DRIVERS FOR THE MELT.

AT THIS TIME...WE COULD SEE SIGNIFICANT RISES ESPECIALLY FOR THE

COTTONWOOD, REDWOOD, MINNESOTA, CROW, MISSISSIPPI FOR ST PAUL

AND DOWNSTREAM, AND THE ST CROIX RIVER BASINS OVER THE NEXT FIVE

TO TEN DAYS. FOR THESE RIVER BASINS...WE COULD POSSIBLY SEE FLOOD

STAGE LEVELS AS EARLY AS THIS WEEKEND AND INTO THE FIRST HALF OF

NEXT WEEK.

FOR THE LONG PRAIRE...SAUK...THE MISSISSIPPI FOR MINNEAPOLIS AND

UPSTREAM...EAU CLAIRE AND CHIPPEWA RIVER IN WISCONSIN...WE ARE

EXPECTING RISES THIS WEEK AND INTO THE WEEKEND. HOWEVER...AT THIS

POINT INDICATIONS ARE THAT THEY WILL REMAIN BELOW FLOOD STAGE FOR

THE NEXT WEEK.

AS CONFIDENCE INCREASES ON THE MELT AND IMPACTS ON THE

RIVERS...RIVER LEVEL FORECASTS MAY BE ISSUED BY THURSDAY WITH FOLLOW

UP RIVER FLOOD WATCHES AND...OR WARNINGS ISSUED AS APPROPRIATE.

PLEASE REFERENCE THE NWS TWIN CITIES RIVER WEBSITE AT

WATER.WEATHER.GOV/AHPS2/INDEX.PHP?WFO=MPX

"Rain shock" ahead?

The big wild card in spring flooding is always heavy rain. There are signs that after a couple of chances for light rain this week, (Today & Wednesday) a stronger rain system may move in late Saturday night and Sunday.

Some models are printing out the potential for as much as 1" of rain with this warm, spring like system.

Heavy rain Sunday? (Click to enlarge)

If we get an inch of rain on top of frozen ground following a week of rapid snow melt, that may "flush" copious amounts of runoff into area rivers & creeks. The resulting "rain shock" can send rivers rapidly higher, and we could quickly transition into rapidly rising rivers with the potential for ice jams and with rapidly fluctuating river levels in the next week to 10 days.

Stay tuned as the flood threat could grow quickly in the next week.

A bad wind in Japan:

Weather and wind conditions seem to have taken an unfavorable turn in Japan.

Let me be the first to say I don't think we really have hard information as to exactly what levels of radiation may or may not be escaping into the atmosphere from the reactors in Fukushima. But news reports of detectable radiation in Tokyo are not good.

At this point in time, we just don't know what the scope of the disaster will eventually be.

What we do know from the Japan Meteorological Agency is that surface winds had been blowing out to seas, but have turned inland over the past day or so. A low pressure system off Japan's east coast has turned winds into a more easterly direction, and that may be carrying radiation emissions in the lowest mile of the atmosphere inland to the west and southwest to more populated areas.

Surface map shows low off Japan's east coast. (Click to enlarge)

Surface winds tredning "inland." (Click for bigger image)

Could emissions reach the USA?

In the event of a bigger release of radiation, some are asking if radioactivity could reach the USA. The short answer is yes. The best answer may be, it depends.

There is an entire sub-science of meteorology called "plume dispersion modeling." I used to work for a firm in Chicago that did environmental consulting in plume dispersion for the nuclear power industry.

In fact, part of my responsibility was to issue detailed wind trajectory forecasts for a nuke plant. That forecast (wind direction and speed) would be used in case of a nuclear emergency such as we are witnessing in Japan. I lived 8 miles from that plant. Talk about a humbling forecast responsibility that hit close to home!

In the event large amounts of radiation were released in Japan above 10,000 feet or so, the prevailing westerly winds would carry the "plume" eastward across the Pacific Ocean toward the USA.

[image]

The good news is the plume would tend to disperse along the way. The bad news is the radioactive isotopes don't decay quickly, and there could be fallout in the USA, especially from rain. I am not a plume dispersion modeler, and therefore unable to make specific forecasts of what might happen in the event of a large release of radiation.

But I can tell you this, people a lot smarter than me will be working on that question.

Bottom line? While there is no need for any action or panic in the USA, the situation is worth keeping an eye on.

Stay tuned.

PH