Friday, September 17, 2010

9/17/10: Friday's Weather Report

Issued at 2:43 PM CDT, Friday, September 17th, 2010

...All headlines issued by the National Weather Service Duluth, Minnesota...

*FROST ADVISORY*

Timing:

3 AM CDT until 8 AM CDT Saturday.

Counties included in the advisory:

Southern Cook MN...Southern Lake MN...Southern St. Louis MN...Carlton MN...Aitkin MN...Crow Wing MN...and Cass MN...

Some cities included in the advisory:

Grand Portage MN...Hovland MN...Grand Marais MN...Finland MN...Silver Bay MN...Two Harbors MN...Duluth MN...Brookston MN...Floodwood MN...Cromwell MN...Carlton MN...Moose Lake MN...Hill City MN...McGrath MN...Aitkin MN...Cross Lake MN...Brainerd MN...and Pine Center MN...

Discussion:

Temperatures are expected to dip into the middle 30s Tonight in the advisory area which will result in areas of frost Overnight into early Saturday Morning.

A frost advisory means that frost is possible. Sensitive outdoor plants may be killed if left uncovered.

*FREEZE WARNING*

Timing:

3 AM CDT until 8 AM CDT Saturday.

Counties included in the warning:

Koochiching MN...Itasca MN...Central and Northern St. Louis MN...Northern Lake MN...and Cook MN...

Some cities included in the warning:

International Falls MN...Northome MN...Bigfork MN...Grand Rapids MN...Hibbing MN...Crane Lake MN...Ely MN...Melrude MN...and Forest Center MN.

Discussion:

Low temperatures are expected to drop into the 27-32 degree range in the warning area which will result in an early Autumn freeze.

A freeze warning means freezing temperatures are imminent or highly likely. These conditions will kill crops and other sensitive vegetation.

Rainfall report for Friday, September 17th, 2010. Source: NWS Duluth, MN.

International Falls MN: 0.37"

Cass Lake MN: 0.16"

Northome MN: 0.23"

Kabetogama MN: 0.27"

3 miles east of Orr MN: 0.15"

2 miles south of Tower MN: 0.15"

Note: The remainder of our local area also saw some showers earlier Today, but rainfall amounts were less than 0.15".

Low temperature report for Friday, September 17th, 2010. Source: NWS Duluth, MN.

Littlefork MN: 34 degrees

Northome MN: 32 degrees

Kabetogama MN: 31 degrees

3 miles east of Orr MN: 28 degrees

2 miles south of Tower MN: 32 degrees

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

A cold front as of 2 PM extended from central Lake Superior through central Wisconsin to far southeast Minnesota with high pressure (early season arctic origin) of 1028 mb centered over western Canada and the northern Rockies. Very cold temperatures with 30s and 40s have plunged south Today into northern and western North Dakota through parts of Montana with Afternoon 850 mb temperatures of zero/-4 degrees C lurking just west-northwest of our local area. Strong F-GEN forcing has caused areas of rain and mixed rain, sleet and snow Today over portions of Montana and western North Dakota. Temperatures were warmer throughout our area Today with highs in the 55-65 degree range with a tight 850 mb temperature gradient in place, ranging from +1 degree C in far Northern Minnesota to +11 degrees C in southern parts of Northwest Wisconsin. Mostly cloudy skies were found in most of Northwest Wisconsin Today due to the cold front moving through that area, more clouds were approaching northern Minnesota from the west This Afternoon, while in between there was a narrow area of clearing in Northeastern Minnesota. Winds Today were out of the north or west at 10-20 mph.

Today's Upper Level Analysis:

Water vapor satellite imagery and RUC model analysis indicates a westerly 500 mb flow in place across the Upper Midwest with a strong mid level jet of 90 knots just off to our northwest-north This Afternoon with an upper level jet >120 knots centered over the Manitoba Lakes and western Ontario Province. Impressive 12 hour 500 mb height falls of 90-150 meters were occurring Today in central Canada near a strong upper level low which was associated with -34 degree C H5 temperatures and 500 mb heights of 5340 meters!

Tonight through Saturday Night:

A strong upper level and surface area of low pressure will move into Hudson Bay Canada through this period while a high pressure ridge stays off to our west/northwest. A strong mid/upper level jet near and north of our local area will cause occasional mid-high level clouds through Tomorrow Night and strong F-GEN forcing moving east out of the Northern Plains Tonight may even generate a few sprinkles or light rain showers Tonight around the Brainerd Lakes, Aitkin and Pine City Minnesota areas. Temperatures Tonight and Saturday Night will be tricky due to the intervals of clouds that will pass through on occasion. Expect mainly 30s and lower 40s for low temperatures both Tonight and Saturday Night, but some 20s are possible in the typical cold spots. Areas of frost could develop Tonight and Tomorrow Night across Northern Minnesota and Northwest Wisconsin with a chance for a killing freeze Tonight from Grand Rapids to the Arrowhead and points northwest of there. High temperatures on Saturday will top out mainly in the 50s. Winds will be out of the west or northwest at 5-15 mph with some higher gusts through Tomorrow Night.

Extended Forecast:

High pressure ridge will be in control of our weather for Sunday and Sunday Night, highs will be in the 50s with lows in the 30s to lower 40s. This ridge of high pressure scoots off to our east for early next week which will be followed by an area of low pressure which is expected to move E-NE out of the western High Plains on Monday and toward western-central portions of Lake Superior on Tuesday. Some rain and possible thunderstorms should develop Monday, but more likely Monday Night and Tuesday Morning across Northern Minnesota and Northwest Wisconsin as this system moves through. Another low pressure system with a farther south track could spread some rain into our area sometime later next week.

5 Day Forecast for Duluth/Superior

*FROST ADVISORY IN EFFECT FOR DULUTH FROM 3 AM CDT UNTIL 8 AM CDT SATURDAY*

.Tonight... Partly to mostly cloudy. Patchy frost possible late, especially away from Lake Superior. Low 35 to 40. Wind northwest to west at 10 to 20 mph.

.Saturday... Partly sunny. High 55 to 60. Wind northwest to west at 10 to 20 mph.

.Saturday Night... Partly cloudy. Low 30 to 35. Wind northwest at 5 to 15 mph.

.Sunday... Partly sunny. High 55 to 60.

.Sunday Night... Partly cloudy. Low 40 to 45.

.Monday... Showers possible. Mostly cloudy. High 55 to 60. Chance of rain 30%.

.Monday Night... Showers at times. A few thunderstorms also possible. Mostly cloudy. Low 47 to 52. Chance of rain 50%.

.Tuesday... Showers possible. Mostly cloudy. High 55 to 60. Chance of rain 40%.

Normal High Temperature Today 64 degrees

Normal Low Temperature Today 44 degrees

Tim