With meteorological summer just about finished, we can now begin to look back at some of our seasonal statistics and compare them to other years in order to see just how warm things really have been for us.  If it seems like we’ve been needing to seek relief in the air conditioning this year a lot more than usual, it’s because we have.  A look at the chart below confirms it.  Here’s a look at a statistic we call cooling degree days that reflects the use or the likelihood of the use of that good old air conditioning.  These numbers really do essentially tell the story:

Cooling Degree Days

   Cooling Degree Days are a value used to estimate energy requirements for air conditioning or refrigeration.  Typically, cooling degree days are calculated as how much warmer the mean temperature at a location is than 65°F on a given day. For example, if a location experiences a mean temperature of 75°F on a certain day, there were 10 CDD (Cooling Degree Days) that day because 75 – 65 = 10.

It looks like we’ll be rounding out the month of August on a warm and humid note, but there will be a brief respite from the heat coming up with the passage of a cold front later this week.  We’ll get at least a short lived break from this heat between Thursday and Sunday.

Posted under climate, heat

As promised, we had some cool, fall-like temperatures across the region to start this morning thanks to a strong area of high pressure that provided us with dry air and clear skies.  That and a cool air mass gave us the perfect set up for good radiational cooling.  Rochester had a morning low of 47° officially while Mason City bottomed out at 44° just before sunrise while Albert Lea reported 46°.  Up north, there were some even colder readings, as you might have guessed, with International Falls reporting a chilly 40° morning low while some spots in the arrowhead of Minnesota were even colder.  Ely reached a frgid 39° this morning while the state’s coldest reading was found in Silver Bay where the temperature dropped to 37°! 

Here are some more local morning low temperatures along with yesterday’s highs from the National Weather Service in La Crosse in their daily climate summary:

MAX/MIN TEMPERATURE AND PRECIPITATION TABLE FOR
THE UPPER MISSISSIPPI RIVER VALLEY
NATIONAL WEATHER SERVICE LA CROSSE WI
808 AM CDT THU AUG 26 2010

…OBSERVATION STATIONS…
VALUES REPRESENT HIGHS YESTERDAY…12-HOUR LOWS…
AND 24-HOUR PRECIPITATION ENDING AT  7 AM CENTRAL TIME
:
:                                 HIGH   LOW   PCPN
:
TOB  : DODGE CENTER AWOS   MN   :   72 /  48 / 0.00
OLZ  : OELWEIN AWOS        IA   :    M /   M /    M
LSE  : LA CROSSE ASOS      WI   :   75 /  51 / 0.00
RST  : ROCHESTER ASOS      MN   :   71 /  47 / 0.00
VOK  : VOLK FIELD ASOS     WI   :   72 /  43 / 0.00
Y51  : VIROQUA AWOS        WI   :   70 /  51 / 0.00
PVB  : PLATTEVILLE AWOS    WI   :   74 /  49 / 0.00
PDC  : PRAIRIE DU CHIEN AWOWI   :   76 /  51 / 0.00
ONA  : WINONA AWOS         MN   :   73 /  50 / 0.00
DEH  : DECORAH AWOS        IA   :   73 /  50 / 0.00
CMY  : SPARTA-FT MCCOY AWOSWI   :   72 /  43 / 0.00
OVS  : BOSCOBEL ASOS       WI   :   77 /  50 / 0.00
MDZ  : MEDFORD AWOS        WI   :   70 /  45 / 0.00
CCY  : CHARLES CITY AWOS   IA   :   73 /  50 / 0.00
AUM  : AUSTIN AWOS         MN   :   72 /  46 / 0.00
FKA  : PRESTON AWOS        MN   :   72 /  52 / 0.00

:…OTHER AUTOMATED OBSERVATIONS…
: VALUES REPRESENT THE 24 HOURS ENDING AT  7 AM CENTRAL TIME
:
:                                 HIGH   LOW   PCPN
:
NEHW3: NECEDAH RAWS        WI   :   74 /  44 / 0.00
YSPI4: YELLOW RIVER PARK   IA   :   76 /  45 / 0.00
BBLW3: BOSCOBEL RAWS       WI   :   74 /  51 / 0.00
BFWW3: BLACK RIVER FALLS RAWI   :   74 /  47 / 0.00
DMLW3: DIAMOND LAKE RAWS   WI   :   70 /  41 / 0.00
NCHW3: NECEDAH 5WNW CRN    WI   :   72 /  44 / 0.00

Posted under climate

Not only are we enjoying a nice, fall-like day today thanks to the arrival of Canadian high pressure, but we’re also celebrating the end of a record streak of warm mornings in Rochester.  This morning’s low, incidentally, was 52° and we have even cooler temperatures ahead for tonight before things begin to warm up for the weekend.  Here’s the statement about that record streak from the National Weather Service in La Crosse:

Record String of Days with Lows at or Above 55 degrees at Rochester MN Ends

    1         55     7/01-8/24 2010
    2         46     6/28-8/12 1916
    3         44     6/28-8/10 1955
    4         43     6/11-7/23 1998
    5         40     7/06-8/14 2006
    6         37     6/28-8/03 1957
    7         35     7/04-8/07 2008
    8         35     7/14-8/25 2007
    9         33     7/07-8/08 2001
   10         33     7/07-8/08 1983

Posted under climate, just cool

Even though we’ve been talking about how “warm” it’s been this summer, and August, we still haven’t officially hit the 90° mark at the Rochester airport for this month. Normal? Eh. We usually rack up 1.5 days in August with highs at or above 90°.

Here’s a look at our other months:
July: 1 (normal: 3.1 days)
June: 0 (normal: 1.7 days)
May: 2 (normal: 0.3 days)
April: 0 (normal: 0.1 days)

But it’s still been warm, right? Yes. Our average temp for August has been 73.6° (that’s highs and lows averaged, FYI), 4.8° above normal. The culprit: a persistant southerly flow that’s kept a feed of Gulf air in the region and warm temperatures (it’s hard to have cool weather when you have dew points hovering near 70° all the time!)

If you need a break from the Gulf summer you unknowingly signed up for, we’ll have one this week. Our temps will drop into the mid….perhaps even..gasp..low 70s!…by the mid week. Dew points will fall into the 40s and 50s and lows will nudge down to the 50° mark by Thursday morning. We’ll round this out with a dry forecast – all in all, a refreshing, pleasant week on tap, especially good with the Minnesota State Fair starting on Thursday.

Posted under climate

For those of you saying, “Don’t go yet, summer temps!”, have no fear. We’re not done with them yet…or the humidity. In the meantime, my words of advice are to get out today and tomorrow before things get warmer & stormy again.

Do you think this summer has been warmer? Cooler? Jeff Boyne at the NWS in La Crosse lays the data on the line for us. And it may surprise you.

Posted under climate

We’ve all had our fair share of active weather and occasional heavy rains, but Wabasha ranks the highest of area reporting stations so far this summer. The 24.21″ of rainfall since June 1st ranks this summer as the wettest in Wabasha’s recorded weather history. This ousts the summer 0f 1993 from the #1 spot with a previous record of 22.21″.

Thanks to the folks at NWS La Crosse for putting together the summary of summer rainfall totals. Click here for the full summary.

Posted under climate, rainfall amounts

If our lengthy warm spell has you wishing for cooler days in the future I have some good news for you, but you may have to be patient…and you may need a parka.  We talked a little last week about the Climate Prediction Center’s latest winter outlook calling for La Nina conditions across our region possibly leading to a colder winter.  Well, the National Weather Service in La Crosse earlier this week sent out its own statement on the subject, giving us a general idea of what this type of pattern means for our own local weather.  According to Glenn Lussky in a typical La Nina pattern, we have a warmer than normal Fall followed by a cooler and drier than normal Winter.  

Here’s the Climate Prediction Center’s La Nina Advisory from last week and below is a chart that shows what the central Pacific’s ocean temperatures will be doing in the coming weeks and months leading up to our La Nina phase.

Cooler water temperatures in the Central Pacific depicted on the latest chart from NOAA point to a La Nina fall and winter.

Posted under climate

Well folks, happy end of July. We had as pretty close to normal of a month as you can get – and a whopper of a difference from our LAST July. I’ll get the specifics up here tomorrow.

Enjoy a toasty, muggy August 1st. We’ll have partly sunny skies with a very small chance of a spotty shower. More rain and storms, at least a better chance, looks to be instore for Monday and Tuesday….

Posted under climate

The Minnesota Climatology Working Group has put together a great overview of June 2010’s rainfall across the State of Minnesota. Note the far southeast corner of Minnesota nearing the 99th percentile in the historical rankings of June 1-28 rainfall.

Posted under climate

June 2010 in Rochester finished with slightly above normal temperatures, but rainfall was way above average. The normal June rainfall is 4.00″ , and this June wrapped up with 7.79″. That puts June of 2010 in 6th place for wettest June on record. The wettest June on record occurred in the year 2000 with 12.52″ of rainfall. The average temperature finished just 1° above average. The average high this past June was 76.1° and the average low was 58.1°.

July Climate
The normal high for July 1st is 79° and the normal high for July 31st is 80°. However, the normal high peaks at 81° on July 17th, so the warmest days of summer are still in front of us.

Based on the 30-year average, July is the wettest month of the year in Rochester with a normal rainfall of 4.61″. The most rain to fall in one day in Rochester, in July, is 7.47″, which occurred on July 11th, 1981.

Posted under climate