Perception vs. Reality
Old Man Winter has a well-developed sense of humor. Now that it's meteorological spring - most of Minnesota has the most snow of the winter season on the ground. With 12 inches on the ground, MSP has seen 45" so far, a little above average, to date. There's 2 to 4 inches of liquid water trapped in that snow pack. The drought is history, right? Sadly, looks can be deceiving.
The ground is frozen, to a depth of 20-40 inches. Until the frost leaves (late April?) all that melting snow won't be able to replenish soil moisture. We have a lot of catching up to do.
State Climatologist Greg Spoden: "As of late autumn the soil moisture content in the plant rooting zone was near an all-time low level at many locations. Without abundant spring rains, a number of critical drought issues involving agriculture, forestry, horticulture, tourism and public water supply will begin to emerge."
Paradox: there's a high risk of moderate to major Red River flooding in the spring, in spite of a long-term drought.
Some hints of spring on the maps: rain Saturday may end as a couple inches of slushy snow Saturday night and early Sunday; 50F+ by the third week of March?
A word to the snow-wise: get out there sooner, rather than later, to play in the best snow of the winter.
Winter Storm Watch. Although most of Saturday's precipitation will fall as rain in the Twin Cities metro, it may begin as rain freezing on contact with cold surfaces, and end as a few inches of slush over central and western Minnesota. Details from NOAA:
...SIGNIFICANT ICING AND SNOWFALL POSSIBLE FRIDAY NIGHT THROUGH SUNDAY MORNING OVER PORTIONS OF WEST CENTRAL AND CENTRAL MINNESOTA... .AN AREA OF LOW PRESSURE SHIFTING EAST FROM THE CENTRAL PLAINS INTO THE MID MISSISSIPPI RIVER VALLEY FRIDAY NIGHT THROUGH SUNDAY WILL SPREAD A MIX OF RAIN...FREEZING RAIN AND SNOW ACROSS WESTERN AND CENTRAL PORTIONS OF MINNESOTA. THE PRECIPITATION WILL START OUT AS A MIX OF FREEZING RAIN AND SNOW FRIDAY NIGHT THROUGH SATURDAY MORNING...MIX WITH AND CHANGE OVER TO RAIN DURING THE DAY ON SATURDAY...THEN MIX WITH AND CHANGE OVER TO LIGHT SNOW SATURDAY EVENING AND CONTINUE THROUGH SUNDAY MORNING. ICE ACCUMULATION OF ONE TENTH TO ONE QUARTER INCH ALONG WITH SNOWFALL TOTALS RANGING FROM 3 TO 6 INCHES ARE POSSIBLE FRIDAY NIGHT THROUGH SUNDAY MORNING. A WINTER STORM WATCH IS IN EFFECT FOR THOSE ALONG AND WEST OF A LINE FROM MORA TO ELK RIVER TO HUTCHINSON TO REDWOOD FALLS.
At-risk Populations: Fine particle pollution is expected to be near a level considered unhealthy for sensitive groups. Populations sensitive to find particles include those with preexisting cardiovascular or respiratory disease, the elderly, children, and individuals who participate in activities requiring extended or heavy exertion, both indoors and outdoors. Members of these groups are encouraged to postpone or reduce vigorous activity and minimize exposure to local sources of air pollution (ie: heavy duty vehicle traffic, wood fires, and candles). Even individuals who are otherwise healthy may experience health effects when pollution levels increase.
Health Impacts: Exposure to high levels of fine particles has been linked with both respiratory and cardiovascular health effects. Fine particles may exacerbate pre-existing health conditions and may cause individuals to experience chest pain, shortness of breath, wheezing, coughing or fatigue. If you experience these symptoms contact your physician.
- February average monthly temperatures in Minnesota were 2-4 F below the historical average. For a number of communities it was only the second time in 21 months that the mean monthly temperature was below average.
- February precipitation totals were above historical averages statewide. Monthly precipitation totals topped the historical average by approximately one-half inch in many locations, and by over 1" in west central and north central Minnesota counties.
- For most of the state, the water content of the snow pack is estimated to be 2-4 inches. Some west central , north central, and northeast Minnesota counties report snow water equivalence values in excess of 4".
- Because of solidly frozen topsoils and high snow water content in west central Minnesota, the National Weather Service warns of a high risk of moderate to major spring flooding along the Red River. This could lead to an ironic paradox where most of the soil profile will remain dry after floodwaters recede.
- The U.S. Drought Monitor continues to place large portions of Minnesota in the Extreme Drought category. In total, 70% of Minnesota's landscape is considered to be in Extreme Drought or Severe Drought. This is down from 84% in late January. A one-category improvement was assigned to some west central and north central Minnesota counties due to heavy February snowfall.
- Despite the amount of water on the landscape, the drought situation will likely remain unchanged until spring. The deeply and solidly frozen soil assures that very little winter precipitation will make it into the ground. As of late autumn, the soil moisture content in the plant rooting zone was near an all-time low evel at many locations. Without abundant spring rains, a number of critical drought issues involving agriculture, forestry, horticulture, tourism and public water supply will begin to emerge.
Alerts Broadcaster Update on New England Storm:
* Snow wrapping around a Nor'easter, capable of 2-5" New York City, as much as 6-8" eastern Long Island. It will be a rough Friday morning commute, but roads should be mainly wet/slushy for drive home Friday PM.
* Boston will see considerably more snow; plowable amounts likely with as much as 5-10" (more western suburbs).
* Significant coastal flooding Friday for Massachusetts as sustained winds reach 35-50 mph: beach erosion and inundation of highways within 7 feet of sea level. Elevated risk of power outages over interior MA and Cape Cod, due to high winds coupled with high water content of snow.
...COASTAL FLOOD WARNING NOW IN EFFECT UNTIL 9 PM EST FRIDAY... * LOCATION...MASSACHUSETTS EAST AND NORTHEAST FACING SHORELINES. * COASTAL FLOODING...MINOR TO MODERATE FRIDAY EVENING... MORE SERIOUS COASTAL FLOODING IS EXPECTED FOR FRIDAY MORNING/S HIGH TIDE WITH MODERATE TO MAJOR IMPACTS LIKELY. MORE SPECIFICALLY ...MODERATE WITH POTENTIALLY AREAS OF MAJOR COASTAL FLOODING IS EXPECTED FOR SALISBURY TO NEWBURY INCLUDING PLUM ISLAND... AND HULL THROUGH SCITUATE AND PLYMOUTH TO SANDWICH. MODERATE IMPACTS ARE EXPECTED ALONG THE NORTH SHORE...BOSTON HARBOR AREA...AND NANTUCKET HARBOR. MINOR TO MODERATE COASTAL FLOODING MAY OCCUR IN SPOTS ON MARTHA/S VINEYARD DURING FRIDAY MORNING. * TIMING....730 AM TO 9 AM FRIDAY...AND 8 TO 9 PM FRIDAY EVENING. THE GREATEST IMPACTS ARE EXPECTED DURING THE FRIDAY MORNING HIGH TIDE...WHICH IS HIGHER ASTRONOMICALLY THAN THE EVENING HIGH TIDES. FLOODING MAY PERSIST FOR MANY HOURS AFTER THE FRIDAY MORNING HIGH TIDE IN LOW LYING AREAS DUE TO THE INABILITY TO DRAIN BACK TO THE OCEAN. * IMPACTS...THE FRIDAY MORNING HIGH TIDE HAS THE POTENTIAL TO BE QUITE DANGEROUS AND COULD BE SIMILAR TO OR IN A FEW SPOTS EVEN WORSE THAN THE FEBRUARY 9 STORM TIDE. SOME AREAS MAY BE INUNDATED WITH 2 TO 4 FEET OF WATER...ESPECIALLY THOSE VULNERABLE TO WAVE OVERWASH. LARGE WAVES MAY CAUSE SCATTERED DAMAGE TO VULNERABLE STRUCTURES...AND SOME EVACUATIONS AS A PRECAUTION MAY BE NECESSARY. SEVERE BEACH EROSION WILL CONTINUE THROUGH FRIDAY MORNING. THE BEACH EROSION MAY BE ESPECIALLY SEVERE ALONG THE OUTER CAPE...INCLUDING CHATHAM...AND ALONG THE EAST SIDE OF NANTUCKET. SOME BEACH EROSION WILL LINGER INTO SATURDAY MORNING. IF ASKED TO EVACUATE...PLEASE FOLLOW THE ADVICE OF LOCAL OFFICIALS FOR YOUR OWN SAFETY AND THE SAFETY OF ANY WOULD BE RESCUERS.
Summary: The storm we've been tracking for 5 days will drop a few inches of slush on metro New York, just enough to make Friday travel interesting with double/triple normal commute times. Some 2-5" amounts are possible, with over 6" east of Plainview and Levittown on Long Island. Some 5-10" amounts are likely in Boston, with 1 foot plus amounts over the far western/southern suburbs. Power outages are likely Friday from Rhode Island into Massachusetts and coastal New Hampshire. Beach erosion and coastal flooding will be most severe over coastal Massachusetts. Winds ease Saturday as conditions rapidly improve.
Photo credit above: "Hackleburg High School in Alabama was destroyed by a tornado in April 2011." (Photograph courtesy Federal Emergency Management Agency.)
Photo credit above: "A living room filled with sand washed in by Superstorm Sandy on Nov. 14, 2012 in Point Pleasant Beach, New Jersey."
Every one of the lakes has endured the winter meltdown:
• Lake Ontario saw the most dramatic decrease with an 88 percent drop in ice coverage.
• Lake Superior lost 76 percent of its ice.
• Lake Michigan saw a decrease of 77 percent..."
* Andrew Revkin has more on this story at The New York Times.
Graphic credit above: "Projected Arctic shipping routes." Photograph: guardian.co.uk
Graphic credit above: "Differences in transit routes for two kinds of vessels (red and blue) enabled by shrinking Arctic ice levels and opening of the Northwest Passage by 2050." (Image: Smith and Stephenson, PNAS, Early Edition)
Graphic credit above: "The concentration of CO2 in the atmosphere measured by Scripps/NOAA at Mauna Loa. We’re rapidly approaching 400 parts per million."
Graphic credit above: "0–700 meter ocean heat content data from NOAA NODC (Levitus) and NOAA PMEL (Lyman) using the same baseline. The yellow arbitrary denialist line is shown, followed by the linear trends for 2003–2012 and 1993–2012 in red. Standard error bars are also shown."