Flood Watch in effect thru Thursday Night… 2-4″ or more possible

Flood Watch with the estimated rainfall from the HPC. Graphic placed together by Todd Nelson of WeatherNation -- thanks!

 A flood watch is in effect through Thursday Night for the possibility of 2-4″ or more of rain from a system coming in from the south that will contain a lot of gulf moisture, allowing for a more June-type rainfall instead of September-like. For today’s set-up, please view my blog from earlier today. Be prepared to get soaked the next few days! And again, thanks to Todd Nelson of WeatherNation for the all in one graphic package!

FLOOD WATCH…CORRECTED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
519 AM CDT WED SEP 22 2010

…HEAVY RAIN POSSIBLE TONIGHT THROUGH THURSDAY NIGHT…

.A FLOOD WATCH HAS BEEN ISSUED FOR TONIGHT INTO FRIDAY MORNING FOR
MUCH OF CENTRAL AND EAST CENTRAL MINNESOTA…ALONG WITH A SMALL
PART OF SOUTHEAST MINNESOTA AND ALL OF WEST CENTRAL WISCONSIN. THE
FLOOD WATCH INCLUDES THE TWIN CITIES METROPOLITAN AREA.

A VERY MOIST AIRMASS WILL SURGE INTO THE REGION TONIGHT AND
PERSIST ACROSS THE AREA THROUGH THURSDAY NIGHT…AS A LOW PRESSURE
SYSTEM MOVES IN FROM THE CENTRAL PLAINS. AS A RESULT… SHOWERS
AND SOME THUNDERSTORMS WILL BE COMMON TONIGHT THROUGH THURSDAY
NIGHT. HEAVY RAINFALL MAY DEVELOP DURING THIS PERIOD DUE TO THE
VERY MOIST AIRMASS AND PERSISTENT SHOWERS.

RAINFALL AMOUNTS BY FRIDAY MORNING ARE EXPECTED TO BE IN THE 3 TO
4 INCH RANGE. THIS AMOUNT OF RAIN ON TOP OF FAIRLY WET SOIL
CONDITIONS MAY LEAD TO FLOODING OF URBAN AND LOW LYING AREAS.

MNZ043>045-048>053-057>063-066>070-076>078-WIZ014>016-023>028-
221830-
/O.NEW.KMPX.FA.A.0001.100923T0600Z-100924T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MORRISON-MILLE LACS-KANABEC-POPE-STEARNS-BENTON-SHERBURNE-ISANTI-
CHISAGO-KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON-
MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA-LE SUEUR-RICE-GOODHUE-POLK-
BARRON-RUSK-ST. CROIX-PIERCE-DUNN-PEPIN-CHIPPEWA-EAU CLAIRE-
INCLUDING THE CITIES OF…LITTLE FALLS…PRINCETON…MORA…
GLENWOOD…ST. CLOUD…FOLEY…ELK RIVER…CAMBRIDGE…
CENTER CITY…WILLMAR…LITCHFIELD…MONTICELLO…MINNEAPOLIS…
BLAINE…ST. PAUL…STILLWATER…HUTCHINSON…GAYLORD…CHASKA…
SHAKOPEE…BURNSVILLE…LE SUEUR…FARIBAULT…RED WING…AMERY…
BALSAM LAKE…RICE LAKE…BARRON…LADYSMITH…HUDSON…
NEW RICHMOND…RIVER FALLS…PRESCOTT…MENOMONIE…BOYCEVILLE…
DURAND…PEPIN…CHIPPEWA FALLS…BLOOMER…EAU CLAIRE…ALTOONA
519 AM CDT WED SEP 22 2010

…FLOOD WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY
MORNING…

THE NATIONAL WEATHER SERVICE IN TWIN CITIES/CHANHASSEN HAS ISSUED
A

* FLOOD WATCH FOR PORTIONS OF MINNESOTA AND WISCONSIN… INCLUDING
THE FOLLOWING AREAS…IN MINNESOTA…ANOKA…
BENTON…CARVER…CHISAGO…DAKOTA…GOODHUE…HENNEPIN…
ISANTI…KANABEC…KANDIYOHI…LE SUEUR…MCLEOD…MEEKER…
MILLE LACS…MORRISON…POPE…RAMSEY…RICE…SCOTT…
SHERBURNE…SIBLEY…STEARNS…WASHINGTON AND WRIGHT. IN
WISCONSIN…BARRON…CHIPPEWA…DUNN…EAU CLAIRE…PEPIN…
PIERCE…POLK…RUSK AND ST. CROIX.

* FROM LATE TONIGHT THROUGH FRIDAY MORNING

* PERIODS OF HEAVY RAIN ARE EXPECTED FROM TONIGHT THROUGH THURSDAY
NIGHT WITH RAIN AMOUNTS OF 3 TO 4 INCHES POSSIBLE.

* RUNOFF FROM THE RAINFALL WILL CAUSE RISES ON STREAMS AND
RIVERS…ALONG WITH POTENTIAL FLOODING DEVELOPING IN URBAN AND
LOW LYING AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A FLOOD WATCH MEANS THERE IS A POTENTIAL FOR FLOODING BASED ON
CURRENT FORECASTS.

YOU SHOULD MONITOR LATER FORECASTS AND BE ALERT FOR POSSIBLE
FLOOD WARNINGS. THOSE LIVING IN AREAS PRONE TO FLOODING SHOULD BE
PREPARED TO TAKE ACTION SHOULD FLOODING DEVELOP.

Flash Flood Watch and Severe Threat Tonight

First, lets tackle today’s severe threat. We are under a slight risk of severe storms later this evening and into the overnight period that encompasses much of Minnesota and stretches into a chunk of Wisconsin. Storms that rolled through this morning popped along a warm front pushing its way into the state today; this is the same boundary that will spark storms later this afternoon and evening. We will have to watch out for hail and isolated tornadoes,  but damaging winds and flooding rains will be the main threats. Read on for the threats and timeline of events.

This is today’s tornado threat. A 5% circle encompasses places from St. Cloud north and west of the area, including Detroit Lakes, the Fargo/Moorhead area, Alexandria, and Wadena areas. It is these areas that will be the start of the storms later today. I think the main threat for tornadoes will be up towards the Fargo area, maybe stretching down into the Alex area. I do not think the STC area has the best chance… can’t rule one out but it is less likely in my mind.

Especially as the storms start popping as quasi-cellular storms, hail will also be a big risk. It is the same areas that are under a 5% tornado risk that are under the 30% hatched hail risk — 2″+ diameter hail is a possibility. More than likely the biggest of the hail will be in storms that get tornado warnings placed in them, and that the hail risk should start to diminish before it reaches the STC area.

This is the wind threat — a 30% circle that includes the STC, Twin Cities, western WI, and the tornado threat area. A couple hours after storms start popping, we expect to see the storms start to form a line capable of destructive winds in excess of at least 60-70 mph. It will be like the 50-70 mph wind event that came through St. Cloud a couple of Tuesdays ago. It is expected to come to life right around/after the dinner hour, and go through the night. The 12z 4km WRF model has the storms starting to pop in western MN around 6 pm, and come roaring through the area around 8-10 pm.

This is a rain estimate from the NAM model, which is outputting over 4″ of rain in areas from Alex to STC to the Twin Cities and southwestward. Even though I would scale back that estimate just a little bit (maybe 3″?) this system is expected to put out a lot of rain in areas.

For that reason, the NWS has put out a Flash Flood Watch for portions of central MN including the STC area, but not yet including the Twin Cities, from 7 PM tonight through 3 AM Sunday morning. I would not be surprised to see Flash Flood Watches and Warnings throughout the evening and overnight over a good chunk of southern MN. I would also expect to see a Severe Weather Watch Box (either Severe Thunderstorm or Tornado) issued sometime during around dinner hour tonight. Will keep you updated throughout the evening on the very latest.

FLOOD WATCH
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
132 PM CDT SAT AUG 7 2010

…HEAVY RAINS LIKELY FOR PARTS OF CENTRAL MINNESOTA LATER TODAY
AND TONIGHT…

.THE NATIONAL WEATHER SERVICE IN CHANHASSEN HAS ISSUED A FLASH
FLOOD WATCH FOR PORTIONS OF CENTRAL AND EAST CENTRAL MINNESOTA
FROM 700 PM THIS EVENING…UNTIL 300 AM SUNDAY MORNING. STRONG
THUNDERSTORMS ARE EXPECTED TO DEVELOP AND MOVE EASTWARD ACROSS
PORTIONS OF CENTRAL AND EAST CENTRAL MINNESOTA LATER THIS
AFTERNOON AND TONIGHT. THESE STORMS WILL LIKELY PRODUCE PERIODS OF
VERY HEAVY RAINFALL…WITH RAINFALL RATES OF ONE TO TWO INCHES PER
HOUR. RUNOFF FROM THESE STORMS WILL LIKELY CAUSE RAPID RISES ALONG
SMALL STREAMS AND RIVERS. PERSONS LIVING IN LOW LYING AREAS OR
CAMPING NEAR ADJACENT CREEKS AND STREAMS SHOULD TAKE NECESSARY
PRECAUTIONS IF FLOODING IS OBSERVED OR IMMINENT.

MNZ041>045-047>053-080245-
/O.CON.KMPX.FF.A.0005.100808T0000Z-100808T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS-
BENTON-SHERBURNE-ISANTI-CHISAGO-
INCLUDING THE CITIES OF…ALEXANDRIA…LONG PRAIRIE…
LITTLE FALLS…PRINCETON…MORA…MORRIS…GLENWOOD…ST. CLOUD…
FOLEY…ELK RIVER…CAMBRIDGE…CENTER CITY
132 PM CDT SAT AUG 7 2010

…FLASH FLOOD WATCH REMAINS IN EFFECT FROM 7 PM CDT THIS EVENING
THROUGH LATE TONIGHT…

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF CENTRAL MINNESOTA…EAST CENTRAL MINNESOTA AND
WEST CENTRAL MINNESOTA…INCLUDING THE FOLLOWING AREAS…IN
CENTRAL MINNESOTA…BENTON…MORRISON…SHERBURNE…STEARNS
AND TODD. IN EAST CENTRAL MINNESOTA…CHISAGO…ISANTI…
KANABEC AND MILLE LACS. IN WEST CENTRAL MINNESOTA…DOUGLAS…
POPE AND STEVENS.

* FROM 7 PM CDT THIS EVENING THROUGH LATE TONIGHT

* THUNDERSTORMS WITH VERY HEAVY RAINFALL WILL LIKELY DEVELOP LATER
THIS AFTERNOON…AND TRACK OVER THE SAME AREAS ACROSS CENTRAL
AND EAST CENTRAL MINNESOTA THROUGH THE EVENING. THIS WILL LIKELY
RESULT IN FLASH FLOODING.

* RUNOFF FROM THE VERY HEAVY RAINFALL WILL CAUSE RAPID RISES ON
SMALL STREAMS AND RIVERS… ALONG WITH FLOODING PROBLEMS IN LOW
LYING AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.

YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.

Flood Watches and Warnings

There will be more on this later tonight and in future days, but currently:

Flood Warning in effect for the Minnesota (at Montevideo, Henderson, Savage), Crow (at Rockford), and South Fork Crow (at Delano, below Mayer) Rivers

Flood Watch in effect for the Minnesota River at Granite Falls, New Ulm, Mankato, Jordan, and Shakopee

All watches and warnings are until further notice. More later.

Dense Fog Advisory through 9 AM Thursday… Rain through Saturday… Watch for Flooding

NWS Chanhassen Watches/Warnings as of 3 PM Wednesday… Gray is Dense Fog Advisory… Lime green is Flood Warning… Dark green is Flood Watch

A series of storms will be affecting the area throughout the beginning of the weekend, leading to many days with periods of rain over the whole area. By the end of the day on Saturday, a half an inch to an inch of rain is possible throughout most of the area from the systems.

These systems will keep the temps above freezing during both the day and night, with highs in the lower to middle 40s and lows in the middle to upper 30s. This will allow for continued rapid snow melt, and I would not be surprised if most snow (except for larger piles) will be melted away by the end of the weekend. One thing we will have to watch out for is rising rivers, especially along the Sauk locally. Meanwhile, a Flood Watch has already been issued for the South Fork Crow River below the town of Mayer affecting Carver County due to the rain and melting conditions.

A Dense Fog Advisory is in effect for parts of Minnesota, including Stearns County, until 9 AM Thursday. Check the statement below for the details.

Tonight Rain and Fog 35. Thursday Rain, especially after noon, and Fog 43. Thursday Night More Rain 36. Friday Continued Rainy 45.

URGENT - WEATHER MESSAGE...CORRECTED HEADLINE
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
210 PM CST WED MAR 10 2010

...DENSE FOG ADVISORY FOR MUCH OF WEST CENTRAL AND SOUTH CENTRAL
MINNESOTA THROUGH TONIGHT...

.A DENSE FOG ADVISORY REMAINS IN EFFECT THROUGH TONIGHT FOR MUCH
OF WEST CENTRAL AND SOUTH CENTRAL MINNESOTA...GENERALLY WEST OF A
LINE FROM SAUK CENTRE...TO HUTCHINSON...TO NORTHFIELD TO RED WING.
VISIBILITIES OF A QUARTER OF A MILE OR LESS WILL PERSIST ACROSS
MUCH OF THE AREA TONIGHT. POCKETS OF NEAR ZERO VISIBILITY ARE
POSSIBLE... ESPECIALLY NEAR THE IOWA BORDER AND THE INTERSTATE 90
CORRIDOR.

MNZ047>049-054>058-064>067-073>075-082>085-091>093-110415-
/O.EXT.KMPX.FG.Y.0009.000000T0000Z-100311T1500Z/
STEVENS-POPE-STEARNS-LAC QUI PARLE-SWIFT-CHIPPEWA-KANDIYOHI-
MEEKER-YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-REDWOOD-BROWN-
NICOLLET-WATONWAN-BLUE EARTH-WASECA-STEELE-MARTIN-FARIBAULT-
FREEBORN-
INCLUDING THE CITIES OF...MORRIS...GLENWOOD...ST. CLOUD...
MADISON...BENSON...MONTEVIDEO...WILLMAR...LITCHFIELD...
GRANITE FALLS...OLIVIA...HUTCHINSON...GAYLORD...REDWOOD FALLS...
NEW ULM...ST. PETER...ST. JAMES...MANKATO...WASECA...OWATONNA...
FAIRMONT...BLUE EARTH...ALBERT LEA
210 PM CST WED MAR 10 2010

...DENSE FOG ADVISORY NOW IN EFFECT UNTIL 9 AM CST THURSDAY...

THE DENSE FOG ADVISORY IS NOW IN EFFECT UNTIL 9 AM CST THURSDAY.

* VISIBILITY...WIDESPREAD ONE QUARTER OF A MILE OR LESS THROUGH
 THIS AFTERNOON.

* IMPACTS...VISIBILITIES WILL BE NEAR ZERO IN SPOTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A DENSE FOG ADVISORY MEANS VISIBILITIES WILL FREQUENTLY BE
REDUCED TO LESS THAN ONE QUARTER MILE. IF DRIVING...SLOW DOWN...
USE YOUR HEADLIGHTS...AND LEAVE PLENTY OF DISTANCE AHEAD OF YOU.

Beautiful start to spring… But melting leads to flooding…

We are going to try and revive my blogging! Woo! For those of you who have followed my blogs for years, you know that I would offer a detailed nightly forecast. Since then I had turned to mainly event-blogging (mainly Winter and Severe Storms). Well I am going to try and mix the old with the new… bring back daily weather thoughts (maybe not complete forecasts or very detailed, but enough to get you through the next day or so) with more detailed writings for the big weather events. We can build this blog together!

Ah, a beautiful day for the start of Spring! Birds chirping, bright blue sky with a bright yellow ball in the middle of it, temperatures in the middle 30s… Yes, a day where t-shirts are actually out in full force. We should enjoy this weather continuing through the rest of the week with highs approaching 40 especially towards the end of the week. We will continue to melt the snow pack that we do have, but just remember that anything that ponds up during the day and doesn’t run off will freeze overnight, so take it safe on the roads in the mornings. We have a chance of a little rain/snow on Saturday, but I’m definitely not expecting much.

We are watching a potential system for the beginning of next week; latest model runs have that sagging southward at the moment. It is still something to keep an eye on, though.

Of course, melting is occurring at the moment — we are down to approximately 11″ of snow on the ground in STC, but there continues to be a deep snow pack to our south and west, ranging over 2′ in areas. Updates within the past week (click on the links for more information) show that there is a good chance of flooding at Montevideo and also the Mississippi River below the junction with the Minnesota River (St. Paul and Hastings); the Crow River at Delano has a large chance of flooding; the Mississippi River above the Minnesota River (i.e. our area) has a 20-40% chance of flooding. Meanwhile, the chance of major flooding along the Red River has increased to 80% in the Fargo-Moorhead area and 60% in the Grand Forks area. While the conditions of the past few days have been ideal melting conditions to minimize the threat, any addition of moisture or rapid increase in temperature will likely increase all these flooding percentages. Also, temperatures in SW Minnesota haven’t been able to get as high as we have the past few days, therefore they haven’t been able to melt as we have been, leading to a lot more increased melting for them as the weeks go on.

Already today, sandbagging is occurring in Fargo and Grand Forks in anticipation of the upcoming flooding which has the potential to come close to last years historic flooding of the Red River. Stay tuned in upcoming weeks for the latest.

Forecast: 10-15 tonight with clear skies. Around 35 Tuesday and continued sunshine.