wxgeek's weather-Dry/Mild here, Frankenstorm for NW-Update

Update Sun Oct 28

A few mid and high clouds drifting across CO today, but we will experience pretty tranquil weather this week, especially compared to the eastern US. Dry weather with temps back to or slightly above seasonal norms through Thursday. Latest models have backed off the precip for later this week now, so perhaps cooler temps by Friday into the weekend, but little if any precip now expected. The following week also now looks dry.

Certainly not the case for the eastern U.S. Hurricane Sandy currently east of Cape Hateras, NC and moving north. Rain already occurring from NC into upstate NY, and will intensify overnight and during then day on Monday from Virginia north to New England. Sandy still expected to become an extra-tropical storm before reaching land, but will continue to intensify until moving over land. The low now looks to cross land near the southern NJ coast Monday evening/night. During the day on Monday torrential rains and hurricane force winds will batter the eastern states along with extreme waves and surf, which will be elevated by a full moon and higher than usual astronomical tides Monday night.

From my perspective this is not a media hyped storm, this is the real deal. Probably the largest and most intense storm to hit a major U.S. population center in my lifetime, certainly in my 30 year meteorological career. Rainfall amounts of 5-15 inches likely which will cause serious flooding, combined with hurricane force winds which will knock out power to millions of people, maybe tens of millions. Height of the storm will be from Monday morning into Tuesday morning, so a good 24 hours of intense rain and wind. Areas just north of the low along the NJ, NY and CT coasts will see the largest tidal surges and waves, some 4-8 foot above normal tides accompanied by 20-30 foot waves offshore. The storm will cause billions in damage, and unfortunately will likely take a toll in human life as well. Local governments are taking extreme precautions, so that will hopefully limit the loss of life. Storm will begin to diminish in intensity during the day on Tuesday when low moves into south central PA. Heavy rains will still continue, and snow in higher elevations of the Appalachians of PA and WV. Low moves north into upstate NY on Wednesday as winds and rain begin to diminish, although some heavy rain still possible in New England and eastern Great Lakes on Wednesday.

Commerce will essentially come to a halt on Monday and Tuesday over the eastern US, with most public transportation suspended, schools closed, businesses closed, most airline flights cancelled, and personal travel discouraged. Life will begin to resume by Tuesday afternoon as utility crews begin to make repairs ans restore power to a vast area. It could be days to a week or more before power is restored to everyone affected. I will hope for the best for everyone in this region.

Lastly, I am headed to an aviation conference in Florida this week, so likely will not post again until Friday.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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So an additional 1 to 6 inches of snow yesterday depending on where you live. Clearing skies today but temps will remain cool, with overnight lows tonight in the low teens to single digits some areas. We will see a gradual warming trend this weekend under mostly sunny skies, although temps likely to remin below seasonal norms. Moderate west to northwest flow aloft this weekend may cause some gusty winds at higher elevations in the mountains and foothills. Winds should be lighter next week.

For next week, upper ridge builds back over the wetsern U.S. which will keep conditions dry across CO with temps warming back to near seasonal norms for most of next week. Next shot at precip according to long range models would be late Friday into Saturday of next week.

Now on the the Frankenstorm scenario for the eastern US. Models continue to suggest an epic storm for the Northeast US Monday into Wednesday of next week. This will be th result of hurricane Sandy, which is presently located near Grand Abaco island in the northern Bahamas, moving parallel to the east coast through the weekend. Sandy is expected to be off the North Carolina coast on Sunday, and then off the Maryland coast on Monday. As Sandy moves north, heavy rain, strong winds and high surf are expected along the mid Atlantic coastal areas. By Monday, factors will come into play that will create Frankenstorm. Sandy will still be a category 1 hurricane, and will be over the warm gulfstream waters. An upper trough with cold air will approach from the west. Normally, this would simply cause Sandy to accelerate and move out to sea. However, a strong upper ridge will build off the eastern Canada coast, which will move Sandy back to the northwest. As Sandy interacts with the upper trough aloft, it will become an "extratropical" storm, so it loses it's tropical characteristics and takes on a more winter storm like structure. A tropical system is warm core based, and decreases in intensity with altitude. A mid latitude storm is cold core based, and increases in intensity with altitude. This transformation of Sandy will create a very deep surface low of around 950 millibars (standard sea levle pressure is 1013 mb) just off the NY coast Monday afternoon. The impact of this deep and large surface low will be felt from Maryland north to Maine, and west to the Great Lakes. Models have some disagreement on timing and where the surface low will make landfall, but it looks like sometime between Monday evening and Tuesday morning somewhere from Rhode Island south to Philadelphia. New York seems a likely target currently. However, the impact area will be large, so it really doesn't matter where the low goes over land like a typical hurricane. Models predict from 5-15 inches of rain in the region, winds will be from 50 to 100 mph, and waves will be from 20-35 feet so this storm will affect a large area, and has the potential to disrupt if not cripple transportation and power to a very large area. Trick or Treating will be replaced by blackness and survival in many areas. Anyone planning to travel to this area next week should seriously consider alternate plans. Travel disruptions will extend far away from this region for a good portion of next week. the storm really does not exit the region until Thursday or Friday of next week. Snow does not look to factor in except in areas much farther west near the Great Lakes and upper Ohio Valley.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for Oct 29 Update