Tuesday, September 14, 2010

9/14/10: Tuesday's Weather Report

Issued at 3:43 PM CDT, Tuesday, September 14th, 2010

All headlines issued by the National Weather Service Duluth, Minnesota

*FROST ADVISORY*

Timing:

1 AM CDT Tonight until 7 AM CDT Wednesday.

Counties included in the advisory:

Koochiching MN...Central and Northern St. Louis MN...Lake MN...Cook MN...Ashland WI...Iron WI...And Price WI...

Some cities included in the advisory:

International Falls MN...Littlefork MN...Northome MN...Hibbing MN...Virginia MN...Ely MN...Crane Lake MN...Two Harbors MN...Silver Bay MN...Isabella MN...Forest Center MN...Tofte MN...Grand Marais MN...Grand Portage MN...Ashland WI...Butternut WI...Hurley WI...Mercer WI...Park Falls WI...Phillips WI...And Ogema WI...

Discussion:

Low temperatures in the 30-35 degree range with isolated spots dipping into the upper 20s are expected in the advisory area Tonight. This will result in areas of frost developing during the Overnight hours.

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

Low temperature report from Tuesday, September 14th, 2010. Source: NWS Duluth, MN.

International Falls MN: 38 degrees

Hibbing MN: 37 degrees

Hayward WI: 37 degrees

Silver Bay MN: 37 degrees

Grand Marais MN: 37 degrees

Eveleth MN: 37 degrees

Babbitt MN: 34 degrees

Embarrass MN: 28 degrees

3 miles East of Orr MN: 35 degrees

2 miles South of Tower MN: 35 degrees

Average first dates of freezing temperatures for Northern Minnesota and Northwest Wisconsin. Source: MRCC (Midwestern Regional Climate Center) Data based on 1971-2000 averages.

Interior portions of Northeast Minnesota and Northwest Wisconsin can expect the first 32 degree minimum temperature between September 11th-20th with locations near Lake Superior having to wait until between September 21st-30th.

The first 28 degree minimum temperature usually occurs between September 21st-30th for parts of Northern-Eastern Minnesota and between October 1st-10th for Northwest Wisconsin while locations close to Lake Superior usually have to wait until between October 11th-20th.

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

The F-GEN induced clouds/light rain showers which passed southeast through portions of our area earlier Today gave way to increasing amounts of sunshine by This Afternoon with skies late This Afternoon ranging from partly cloudy-sunny with some cumulus affecting far Northern Minnesota while some mid/high level clouds continued to pass through southern portions of our area. A ridge of high pressure averaging 1018-1024 mb extended from Saskatchewan Province through Central Wisconsin toward the Ohio Valley while several areas of low pressure of 1010-1014 mb were centered over the Central Rockies. High temperatures Today were in the middle 50s to middle 60s across Northern Minnesota and Northwest Wisconsin with late Afternoon dewpoints in the 30s and 40s along with PWS of 0.40-0.80". Winds Today were calm or variable in direction under 15 mph.

Today's Upper Level Analysis:

A nearly zonal 500 mb flow (west-east) covered the Upper Midwest Today per water vapor satellite imagery with upper level troughing in place across Northeastern Canada while another rather vigorous trough advances E/NE through the Northern-Central Rockies late Today.

Tonight:

Skies This Evening will remain mostly clear-partly cloudy with increasing clouds taking place from west to east Overnight. High pressure ridge will remain to our northwest/east Tonight while low pressure and a potent trough approaches the Western High Plains. A few showers could develop late Tonight along and south/west of a line from Backus to Shell Lake. Lows Tonight will be in the 30s and 40s with some 20s possible in the typical cold spots. Areas of frost will develop late Tonight especially in Northern Minnesota and in eastern sections of Northwest Wisconsin. Winds Tonight will be calm or variable in direction under 15 mph.

Wednesday and Wednesday Night:

An area of low pressure is forecast to track east-northeast out of the Western High Plains, reaching the area between Madison Wisconsin and Chicago Illinois by Wednesday Night. A 90-120 knot upper level jet to our northeast combined with the surface low passing by to our south will provide plenty of lift which will lead to widespread rainfall for portions of our area. At this time it appears that the majority of the rain with totals >0.01" will fall along and south of a line from Bemidji to Hibbing to Grand Marais with the heavier rains with possible amounts reaching 1.00" affecting areas from Central and Eastern Minnesota through Northcentral Wisconsin. Locations north of the Iron Range could see a few light rain showers or sprinkles at times Tomorrow and Tomorrow Evening, but the bulk of the steadier rain is expected to remain south of those areas. Mostly cloudy skies are forecast on Wednesday with highs generally in the 50s, maybe a few 60s in far Northern Minnesota.

The best chance for rain Wednesday Night will occur during the Evening hours with mainly dry conditions returning to our area during the Overnight. Partly-mostly cloudy skies with lows in the 30s and 40s can be expected Tomorrow Night. Winds will be out of the east or north at 10-20 mph during this period.

Extended Forecast:

A fairly strong cold front is set to pass through our local area Thursday Night and Friday with an early season dose of arctic air with highs in the 30s/40s (850 mb temps of -4/-10 degrees C) remaining to our northwest late this week into the weekend. Some showers could accompany the cold front as it moves through our area from Thursday Night into Friday. High temperatures will be in the 50s and 60s for Thursday and Friday with some spots in far Northern Minnesota possibly holding in the 40s on Friday. Low temperatures will be in the 40s for Thursday night with 30s and 40s expected for Friday Night. Appears that our next threat for rainfall will come sometime late this weekend or more likely early next week.

5 Day Forecast for Duluth/Superior

.Tonight... Mostly clear with increasing clouds late. Low 40 to 45. Wind variable, becoming east at 4 to 12 mph.

.Wednesday... Occasional rain developing. Mostly cloudy. High 52 to 57. Wind east at 10 to 20 mph. Chance of rain 70%.

.Wednesday Night... Occasional rain ending early. Mostly cloudy. Low 40 to 45. Wind northeast to north at 10 to 20 mph. Chance of rain 50%.

.Thursday... Partly cloudy. High 58 to 63.

.Thursday Night... Partly to mostly cloudy. Low 45 to 50.

.Friday... Showers possible. Mostly cloudy. High 58 to 63. Chance of rain 30%.

.Friday Night... Mostly cloudy. Low 40 to 45.

.Saturday... Partly sunny. High 50 to 55.

Normal High Temperature Today 65 degrees

Normal Low Temperature Today 45 degrees

Tim