We can trace this back to the April 27 Tornado outbreak, that upper low crossed New England April 30th, then stalled off shore as
a Blocking weather pattern became established in The Northern Hemisphere. On May 3rd, the old tornado storm stalled north of Bermuda with a 1006 millibar surface low generating a nice groundswell, first good surfing of spring 2011. That low became part of a weather traffic jam, causing the next front that arrived here on May 5th, to stall over Maine the final 3" of snow in our mountains (same day Sox lost 11-0 to Angles, we had a Rainbow over the Pru, and hail on Cape Cod.) Two days later the same upper low absorbed the next front here on Saturday May 7th, with widespread major hailstorms here. Each of those two weekends our Blog contained the phrases, 'blocking pattern' and 'the last weekend of skiing for New England'. Here we are tow weeks later, and not much has changed.
Bill Stenger, owner of Jay Peak Resort Vermont opened two trails for skiing again. Even with only a handful of skiers and steady rain today, Sunday May 15th, Bill said "Let Them Ski" (Amen Bill, we love you BigBro). This really should do it for lift served skiing in New England (Tuckerman's is full of snow though). As for the Blocking Weather Pattern? When this will end, nobody knows.
The cut off from last weekend moved just far enough offshore that much of New England had nice weather this past week. But along the shore we saw clouds with Heavy Surf and occasional rain Tuesday through Thursday. The Satellite image looked as if we had a Hurricane north of Bermuda. Thanks to a weak tide, no coastal problems were reported, but it sure was cool and gray, with clean overhead sets by Thursday, and Great Surf and Sunshine Friday. The reason I am backtracking is to set the stage for this upcoming week. Two weeks ago the storm was weak and way out, this past week, the storm was strong and closer, so guess what happens this week? The storm may be weak, but it is stalled south of New England. This storm is the same one that dropped the 700th inch of snow in the High Sierra to The Wasatch Range. It took the entire week to cross the country, and will be here until Friday.
We are experiencing Gully Washers today with Rainfall Rates .5" to 1" per hour in slow moving showers and storms. Lake Champlain Valley has 1"-2" of new Rainfall, with Lake Levels now rising again, a new crest of about 102.5' is forecast for about May 25th, this would be shy of the record crest of 103.2 on May 6, 2011. But the wind is whipping on the Lake Today, with 2'-'4' waves lapping the hundreds of Lakeside properties now flooded.
The heaviest rainfall is likely to be today and tonight, with a general 1-3 inches. But the upper low will be sending spokes of rain from south to north for us through Thursday. An additional 1-3 inches will push the weekly total to 2"-5". Outside The Champlain Valley, major flooding is not expected. Though this weather set up is similar to the Record New England Flood of May 2006, 5 years ago this week. In 2006 we had more of a gradient between tropical air overrunning polar air. This year the warm is less humid, and the cold is less cold, so we 'should not' see a repeat. The air is cold enough though, that we may have some sleet mixed with rain in Northern Aroostook County Maine earl Monday Morning.
The most interesting feature with this storm is the Cold Front moving north to south across New England Tonight. How can upper level wind be from the south, yet a cold front moving in from the north. It's the Density and Atmospheric Pressure. There is another (different from the ones listed) Upper Low in Northeastern Quebec, the backside of that low is pushing Polar High Pressure system into southern Quebec, with the weather traffic jam, it gets stuck, and strengthens. Watch the Barometer rise here the next few days, rising barometer means falling thermometer. The heavy (more dense) cod air is undermining the light (less dense) warm air. This is the reason we have a cold front pushing south even as upper level wind is steering north. This mechanism causes upward vertical motion, which causes cooling, condensation and rain. It's overrunning rain. Back in 2006, we had band stall over the Merrimack Valley. This year we have a band stalling from the Maine Mid-Coast to central Vermont tonight, but the band 'should' break up tomorrow.
The gradient between the stalled 1026 millibar low to the north, and the 1002 millibar low south, is not strong enough for damaging wind. But the orientation is such that we get persistent wind from the northeast for Monday-Thursday. The full flower moon is Tuesday. The highest tides of the month are midnight Monday and Tuesday (~12.2' Boston). This will cause minor coastal flooding, and minor to moderate erosion along east facing shores. This is worse than last week because of the moon (and because of last week).
So when do we see sunshine? The readers on Cape Cod of let me know.. 'The sun is out today buddy, where do you get your information?' Well we have glimpses here and there, especially Thursday-Saturday. But the next dry day for New England may not be until next Sunday. Guess what happens the next week. There is snow falling at Sandberg CA today, that is only at 4,524 feet above the Pacific Ocean in Los Angeles County CA. Yup snowing in Southern CA today. This Pacific storm is stronger than the one from a week ago. Stuck in Bumper to Bumper Weather Traffic, the storm may not get here until Monday May 23rd. Along the way it will make headlines crossing the country with more snow, floods, and severe weather.
I spoke to Joe 'King of Long Range Forecasting' D'Aleo today. He says we are in for a chilly wet summer, with a chance of a hurricane. Joe also says he does not mind this wet week. He planted grass seed, and a robin just laid eggs in the tool rack of his grill. Not even the dog is allowed on the porch.