Opti Forecast 7/21

Sailing Weather Forecast

Optimist Nationals

Lake Minnetonka, MN

Issued: 0700LT Saturday, 21 JULY 2007

 

REQUEST: Feedback is an important part of the process toward improving weather forecasts. Please send daily weather notes and feedback to msanders@sailwx.com. Thanks!

 

WEATHER RISKS: There are no active weather warnings or advisories for the sailing area.

Please tune your VHF to NOAA Weather Radio for the latest official warnings and advisories.

 

Synopsis: Yesterdays forecast generally unfolded as planned with the wind speed only a knot or 2 below the forecasted range in the early afternoon. However, late in the day this very light air proved to be a bit shiftier than predicted with the direction varying between S and E rather than holding to the forecasted SE flow.

 

Very ideal Optimist sailing conditions are on tap for today. High pressure centered to the east over Lake Michigan provides mostly sunny skies and more importantly a steady southerly flow that builds in speed through the day on Lake Minnetonka. High pressure influences the weather over Minnesota for several days to come so the pleasant conditions continue along with building heat and humidity each day.    

 

Current Conditions: Winds have been out of the SSE since midnight. At 0630 observations from MYC, Minneapolis, and Flying Cloud continue to indicate a SSE-SE wind at 03-06 kts.    

 

Satellite images depict a few scattered clouds that are dissipating as the sun rises and visibility remains at 10 miles or greater across the region.  

 

Forecast Discussion: The theme of the day is a SSE-S wind that builds in speed through the late morning and afternoon. The light air of this early morning builds the next several hours so that by 0900 expect a SSE wind at 08-12 kts. Come 1200 a slight right shift is likely so that a more southerly wind prevails as speeds increase to 10-14 kts with gusts to 18 kts. During the mid afternoon, near 1500, wind speeds should be greatest at 11-15 kts with gusts to 20 kts out of the S. Speeds decline slightly to 09-13 kts by 1800 but remain southerly.    

 

Weather: Sunshine and blue skies continue through the day with a few cumulous clouds likely during the afternoon. Temperatures warm to a high near 83 F and it will be a bit muggier than yesterday as the humidity increase. Sunscreen is again necessary with a high UV index of 9-10.   

 

Seas: The calm seas of early this morning should gradually build as the wind increase so that by late morning and though the afternoon expect some slightly choppy conditions.

 

Detailed Wind Forecast for Today (07/21/2007):

Time(LT)  Wind Speed    Wind Direction 

1000      09-13         SSE  

1100      09-14         SSE         …build in speed underway

1200      10-14         SSE-S       …small right hand shift

1300      10-14         S

1400      10-15         S          

1500      11-15         S           …max winds of the day, gusts to 20 kts

1600      11-15         S    

1700      10-14         S           …declining wind late in the day

1800      09-13         S

 

Hedge: Forecast confidence is AVERAGE for wind speed and ABOVE AVERAGE for wind direction. The wind will be not be as shifty as yesterday but in a southerly flow the best breeze remains over the center and northern portion of the lake. Winds will be lighter and shiftier near the southern shore and along the eastern shoreline they may veer to a more SE-ESE direction. Overall this will be a much better sailing day than yesterday with a steadier and stronger wind.  

 

Sunday (22 JULY 2007): Good sailing conditions continue tomorrow as the steady southerly wind continues. In the morning hours expect 08-11 kts from the south building to 10-15 kts by midday with gusts to 20 kts. The wind continues from the S through the afternoon at 12-16 kts early, easing to 09-13 kts late.

 

Detailed Wind Forecast for Sunday (07/22/2007):

Time(LT)  Wind Speed    Wind Direction

1000      08-11         SSE-S

1200      10-15         S

1400      12-16         S

1600      11-15         S

1800      09-13         S

 

Weather: High pressure extends through the Great Lakes and into Minnesota tomorrow. A small disturbance tracking through the northern part of the state is likely bring a mix of sunshine and clouds to Lake Minnetonka with the slight chance of a shower or thunderstorm. Temperatures increase to a high near 88 F and it will feel muggier.  

 

LONG RANGE OUTLOOK

 

Monday (23 JULY 2007): Winds turn SSW in the morning from 04-07 kts and then continue to shift right to the SW at 05-10 kts during the afternoon. Sunshine mixed with clouds, possibly a late day shower, and a high of 91 F.  

 

Tuesday (24 JULY 2007): A S to SE wind through the day, light at 02-06 kts in the morning, increasing to 05-10 by midday and through the afternoon. Sunshine with a few clouds and a high of 90 F.   

 

Wednesday (25 JULY 2007): Expect a persistent SE flow building from 02-05 kts early to 07-11 kts by midday. A high near 92 under mostly sunny skies.