Heavy Snow – Storm Prediction Center Mesoscale Discussion 2106

Storm Prediction Center Mesoscale Discussion 2106.

1155 AM CST WED NOV 07 2012

AREAS AFFECTED…PARTS OF THE TRI-STATE AREA OF CT/NY/NJ – CONCERNING…HEAVY SNOW – VALID 071755Z – 072100Z

SUMMARY…A BAND OF MODERATE TO LOCALLY HEAVY SNOW SHOULD PERSIST THROUGH ABOUT 20-21Z WITH RATES APPROACHING 1 IN/HR. OTHERWISE…A BROADER TRANSITION TO SNOW IS EXPECTED WITH RATES NOT EXPECTED TO REACH 1 IN/HR.

DISCUSSION…METARS CONFIRM MODERATE TO LOCALLY HEAVY SNOW ASSOCIATED WITH A BAND OF ENHANCED RADAR REFLECTIVITY FROM NEAR NYC TO HARTFORD. THIS APPEARS TO BE LOCATED ALONG THE EDGE OF THE 850-700 MB JET AND ASSOCIATED FRONTOGENETICAL FORCING. GUIDANCE IS CONSISTENT THAT THIS ASCENT WILL WANE SOMEWHAT DURING THE AFTERNOON. THIS WILL LIKELY MITIGATE AN APPRECIABLE INCREASE IN SNOWFALL INTENSITY DESPITE A TRANSITION TO SNOW OVER A BROADER AREA AS THE THERMODYNAMIC COLUMN COOLS AOB FREEZING. AS SUCH…SNOWFALL RATES SHOULD PEAK NEAR 1 IN/HR FROM NOW THROUGH ABOUT 20-21Z.

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#Sandy Makes Landfall October 29 2012 – Graphics

Sandy has made landfall as an Extratropical storm on the southern tip of New Jersey near Cape May and Ocean city. At landfall Sandy had Sustained winds of 90 mph and a central pressure of 940mb. Tropical Storm Force and Hurricane Force winds were felt for many hours. The National Hurricane Center has Sandy as a Post-Tropical Cyclone making landfall at 8:00 PM EDT Monday, October 29 2012 with winds of 80 mph and a central pressure of 946 located at 39.4N 74.5W. and moving WNW AT 23 MPH .[see note at bottom of post]

Below is the ONLY graphic from the Hurricane center of Sandy before landfall at 5:00 PM EDT Monday, October 29 2012. There is not a graphic at landfall at 8:00 PM EDT. Notice the location on the graphic 38.8N 74.4W and moving WNW at 28 mph as compared to the location at landfall from above 39.4N 74.5W. and moving WNW AT 23 MPH.

So the storm was moving at 23 mph at landfall, a decrease of 2 mph from the 5 pm report. Yet it took according to the Hurricane center 3 hours from the 5 pm report to make landfall at 8 pm, moving less than 34.4 miles at 23 miles and hour. Where as at 23 mph X 3 hours would have moved it 69 miles. I contend Hurricane Sandy made landfall between 6:15 and 6:30 pm as reported to my followers here, on facebook, and twitter as an Extratropical storm. Apples and Oranges, I know.

Here are Satellite images of Sandy During landfall from 6:15 PM EDT, 7:45 PM EDT and 8:15 PM EDT.

Sandy SAT 615 pm EDT 102912

Sandy SAT 745 pm EDT 102912

Sandy SAT 815 pm EDT 102912

Note – Landfall : The intersection of the surface center of a tropical cyclone with a coastline. Because the strongest winds in a tropical cyclone are not located precisely at the center, it is possible for a cyclone’s strongest winds to be experienced over land even if landfall does not occur. Similarly, it is possible for a tropical cyclone to make landfall and have its strongest winds remain over the water. Compare direct hit, indirect hit, and strike. source – http://w1.weather.gov/glossary/index.php?letter=l

Many including myself thought from looking at data at the time that Hurricane Sandy made landfall between 6:15 and 6:30 PM EDT Monday October 29 2012; including some pro Mets. However the official time of landfall for Hurricane Sandy as released by the National Hurricane Center was at 8:00 PM EDT Monday October 29 2012. I will also point out that http://www.nhc.noaa.gov/aboutgloss.shtml#l the National Hurricane Center tells us the same thing as the first link above from weather.gov. …. Now from observations, Hurricane Sandy or as it was called at landfall, Post-Tropical Cyclone SANDY, made landfall after the WHOLE EYE was on land. Not the leading edge. Not the center. The complete eye, at 8 PM EDT Monday October 29 2012

Hurricane #Sandy Making Landfall – 10/29/12

Currently – Winds: 90 mph | Pressure 940 mb | Location: 38.8N 74.4W (30 miles East-southeast of Cape May New Jersey and 40 miles South of Atlantic City New Jersey) | Moving Northwest at 28 mph. Tropical storm force winds extend out 485 miles and Hurricane force winds out 175 miles from the center.

Sandy is still off shore at this time. She is continuing to head to the north-northwest at 28 mph. Sandy is headed for Cape May New Jersey and the Delaware Bay area. Reminder: When we talk about landfall, we are speaking of the center of the storm. Sandy is large and as many of you know, her winds and rains have been felt much of the day. So the center is not that important.

Below shows Storm Radial Velocity measuring wind speed and Base Reflectivity Radar showing rain.