**IMPORTANT AND POWERFUL STORM APPROACHING THIS WEEKEND INTO THE EARLY WEEK
There is a major coastal storm that's going to form over the gulf, tracking up the east coast, bringing tons of moisture along with it. Timing: Sun-Mon. Impacts are: Heavy Rain, 2-3", locally up to 5", isolated areas with precipitation rates up to 1" per hour in heavier bands; High winds, the track of this storm can alter the winds greatly, still, high winds are expected. There are two scenarios that can happen:
Scenario #1:
Scenario #2:
Even if the winds are weaker than expected, damage could be done to due the sprouting of many deciduous trees in our area. Downed trees are expected to be scarce because the soil is very dry, despite the rain that we will get.
RWSSS (Relative Wind Storm Severity Scale): Category 3 - Highest sustained wind of 35-40mph or highest gust of 55-60mph
Update: At first, it appeared that this storm was more likely to take the track demonstrated in Scenario #1, however, the latest model runs of the NAM, GFS, and the ECMWF show the storm taking a similar track of Scenario #2, this could potentially increase the winds over the New York metropolitan area and elsewhere. The NAM model is predicting sustained winds of 30-35kts over Central Long Island early Monday morning; the GFS and the ECMWF are predicting weaker winds ~ 20-30kts. Considering the fact the models are indicating a more inland track and higher winds, this pattern may continue, and the forecast winds may increase on the GFS and the ECMWF and would be equivalent to the NAM's forecast winds. If the winds described on the NAM happen, it is likely that the NWS will issue a High Wind Warning, which would make this storm severely life threatening with the trees full, similar to Hurricane Irene. I will continue to monitor new model runs and bring new updates to this thread as more data rolls in, and as the storm develops.
Update#2 (3:49PM 4-21-12): The NWS has increased their wind forecast for Sunday night, they are now expecting wind gusts as high as 50mph. The original forecast was wind gusts as high as 35mph
Update #3 (6:32PM 4-21-12): The GFS isn't predicting strong winds like the NAM is, this is according to the 18z model runs. The GFS predicts the storm to have a large center of circulation while the NAM shows the storm with a small center of circulation; a smaller center of circulation will cause stronger winds. Unfortunately, it is hard to predict what will happen, I'll just have to monitor the storm as it develops. FLOOD WATCH in effect:
... Flood Watch in effect from Sunday afternoon through Monday
morning...
The National Weather Service in Upton has issued a
* Flood Watch for all of southern Connecticut... northeast New
Jersey and southeast New York...
* from Sunday afternoon through Monday morning.
* Rainfall with a cold front passing through tonight should be
less than a half inch. This front will then stall just to the
south on Sunday... and serve as the focus for heavy rain Sunday
afternoon as an intensifying coastal storm moves northward and
transports considerable Atlantic moisture along with it.
* Rainfall with the coastal storm will begin Sunday morning... and
become heavy at times later Sunday afternoon. The heaviest rain
should occur during the first half of Sunday night in the New
York City metropolitan area... western Long Island and the lower
Hudson Valley... and overnight Sunday night in southern
Connecticut and eastern Long Island... with hourly rainfall rates
approaching an inch per hour in the heaviest rain bands.
* Total rainfall of two and one half to three and one half
inches... with locally higher amounts... could cause significant
flooding of urban and poor drainage areas... and flooding of fast
responding small streams. Hard dry ground due to lack of recent
rainfall... and storm drains that have not yet been cleared of
winter debris... may actually contribute to additional runoff in
these areas. Main Stem rivers are unlikely to experience
flooding.
Precautionary/preparedness actions...
A Flood Watch means there is a potential for flooding based on
current forecasts. You should monitor later forecasts and be
alert for possible flood warnings. Those living in areas prone to
flooding should be prepared to take action should flooding
develop.
Goodman
