Dave Zaff

@davidzaff.bsky.social

393 Followers 420 Following

Meteorologist. I like snow, all kinds. Except blizzards. I don’t like blizzards.

Two images of Earth, via NASA (Artemis II). The one on the left shows a dim view of Earth with a clear bright arc on side indicating that the planet will soon be illuminated by the sun. The one on the right, presumably the same image, appears to be brightened to show more details.
A NWS Dodge City tweet from March 13, 2021 with a single word reply, “No.”
KCCX radar displays an arctic front barreling east-southeast across central PA.
The official NWS forecast showing the probability of precipitation for Saturday using the 733 AM issuance showed a 50% chance for at least 0.01” of rain for the D.C area through 600 PM,
A search for ‘NOAA’ in today’s news turns up multiple troubling articles regarding cutback, along with other issues.
Shelf cloud above East Aurora NY.
Widespread low clouds slowly decrease inward toward the center of Lake Erie until skies are clear. Images are in 20 minute intervals from 12Z-1820Z April 30, 2025.
There is a 30-44% chance of severe weather over Western NY and PA on Tuesday, April 29, 2025, and a 10% chance for significant severe weather, defined as: A tornado that produces EF2 or greater damage. Wind speeds of 75 mph (65 knots) or greater. Hail 2 inch in diameter or larger.
While most of Central NY is covered by low-topped cumulus clouds under westerly flow, there is a thin strip east of Oneida Lake that's nearly cloud-free due to the cool water with slightly warmer surrounding landmass.
www.timeanddate.com provides excellent information about upcoming eclipses. This screenshot shows how much of the sun will be covered by the moons shadow at 7:05 AM at Buffalo, NY. Not much.
This satellite image taken on 3/21/25 shows ice cover over the eastern end of Lake Erie, along with a thin strip of ice stretching from Long Point, Ontario to the larger area of ice.
This GOES-16 visible image loop shows moving ice cover on the eastern side of Lake Erie. Images were taken at 1/2 hr time steps from 12-18Z on 03/18/2025.
PTDS showing the probability of the Tornado Detection Signature heading for Bassfield, MS at 107PM CDT (1807Z) 03/15/2025
A cloud animation over the Northeast US from the 03/13/2025 12Z HREF valid between 04-09Z tonight. The image loop mostly shows some increasing high clouds, with coverage between 10-40%. Lower cloud percentage is around 10%. No mid clouds are forecast overnight.
Numerous cloud hole punches, probably from aircraft flying in and out of Toronto through a relatively thin layer of clouds around 10,000 ft.
Leprechaun Canyon
Synthetic Aperture Radar (SAR) Wind data, while not a perfect match for ice cover (as it's designed for wind, not ice), shows the open water areas in blue. This image shows notable open water areas east of the Lake Erie Islands and north of Long Point.
A plume of lake effect snow can be found across Central Erie County, NY around 11:30 AM on February 19, 2025
An image showing 27% ice cover over Lake Erie from January 18, 2025 fades into one with 80% ice cover from January 23, 2025.
Seasonal snowfall statistics for the CoCoRaHS station: NY-ER-50. The average snow based on this station is 103". The lowest value was a paltry 39.5" between 2011-2012 (moderate La Nina), with a peak of 185.3" for the 2014-2015 season (weak El Nino), much of it based on the epic snow event in November 2014 and subsequent synoptic and lake effect snow events in Jan-Feb, 2015.
A Dprog/Dt (the change in a model's forecast for a given valid time over a period of time) shows increasing confidence for a significant snow event over the Gulf coast and Southeast US. The SOT remains near/on the north end of the eventual snow path, while the EFI starts to light up over Houston and areas east along the Gulf coast.
A video in Western NY shows heavy snow falling in a backyard with over 18 inches of snow on outdoor furniture.
Synthetic Aperture Radar (SAR) imagery from 1/21/205 with normalized radar cross section (NRCS) shows a notable ice buildup over the western side of Lake Erie, with shore ice on both the north and south sides of the Lake.
Buffalo NY radar shows a strong single band lake effect snow event with a lightning overlay. A single strike is over Lake Erie.
Forecast for Atlanta, GA
NCRS, or normalized radar cross section, shows ice over the west end of Lake Erie. Shore ice can also be seen along the Ohio shoreline.
Lake Erie Average Ice Cover and current ice cover. The lake is a little below average to date for ice, but that can change fairly quickly with arctic blasts. The average current lake temperature (not shown) is about 33F.
GOES-19 loop between 1821-2011Z on Jan 7, 2025 at 10 minute time steps using the CIRA Fire Temperature product shows a rapidly intensifying heat source near Palisades, CA.
The analog map is centered on a 8-14 day period. So focusing specifically on Jan 9, 2025 isn't a great idea. The analogs show a history of mostly notable and localized lake effect events with this type of pattern though, shown in order of best match. Jan 18, 1985 - Buffalo "6 pack" blizzard Dec 27, 2000 - highest amounts (3+ feet) in Oswego County Jan 16, 1977 - the "other" Blizzard of 1977 Jan 04, 1981 - minor event Jan 26, 2007 - nothing too impressive - multiple minor events Jan 23, 1985 - Buffalo "6 pack" blizzard (part II) Jan 09, 1985 - no data Dec 23, 1985 - lake effect events prior to and after this date Jan 25, 1977 - a few days prior to the infamous Blizzard of 1977 Dec 27, 2001 - the too-white Christmas (7' in 5 days)
12Z Dec 24, 2024 500mb heights and anomalies forecast from the Canadian ensemble valid 12Z Wed Jan 8, 2025. The pattern with an anomalous longwave ridge in the west and a corresponding Great Lakes trough usually favors a lake response. In this case, the trough would favor a WNW or NW flow over eastern Great Lakes. Timing this far out is of course nearly impossible, but it provides some scenarios.
A blizzard raged across Western NY between Dec 23-25, 2022. This picture was taken outside the NWS Buffalo office in the middle of the event on Dec 24, 2022. In the foreground, there’s a picture of the NWS Buffalo sign. In the background, a stranded car.
A park bench in East Aurora‘s Majors Park is half buried in snow. The surrounding trees are glittering with frost in the morning sun.
All four clusters showing 500mb heights have a West Coast ridge and Great Lakes trough by Dec 22, 2024.
A picture after an intense lake effect snow band dropped 2 feet of snow over Western NY on December 12, 2024. The picture shows 2 feet of snow on top of a garbage bin.
24” of snow in 12 hours ending at 11:00 AM in East Aurora, NY.
KBUF radar shows a stationary intense narrow band about ~12 miles wide at 9:35 AM Dec 13, 2024.
A 500mb cluster forecast from Dec 2 valid Dec 12. Clusters 2 and 3 had a long wave pattern supportive of a lake effect.
Lake effect snow outside Buffalo NY east of Lake Erie has been persistent this past week. This video shows roughly 5 second clips of me shoveling or snow blowing snow on November 30th, December 1st, and December 4th-7th. I was traveling on December 2nd-3rd.
A sharp snow line can be seen from Lake Erie northeast across Buffalo and Buffalo's so-call Northtowns where the ground is bare. To the south of this line, heavy snow occurred. This is viewable from satellite imagery.
A NAEFS 500 mb forecast from Nov 20 earlier last month valid at Nov 30, 2024. The pattern showed a large ridge over the western US with a trough over the Eastern US. This pattern favors a lake effect response downwind of the Great Lakes. (NAEFS: North American Ensemble Forecast System, made up of a bunch of Canadian and GFS members averaged together)
The town of Cassadaga NY reported 54.1" of snow, over 4 feet, over 4 days by 6 AM December 2, 2024.
A bird takes some food from an available bird feeder during a lake effect snow event.
A single GOES-16 image clearly shows a full fetch primary lake effect band lined up along the entire length of Lake Erie. This image was taken at 1511Z on Dec 1, 2024.
3 feet of snow has now been reported east of Lake Erie, with 37.6 inches at Perrysburg, NY.
Radar pic from Kansas City earlier this morning showed an impressive narrow band of snow.
Snow reports east of Lake Erie across Western NY.
So total lack so far from a lake effect snow event east of Lake Erie into Western NY
31.6 inches reported at Cassadaga Ny this morning from a lake effect snow event off Lake Erie.
Various posts from the Thruway Authority explaining various highway closures.
The NYS Thruway closed into PA. A section of I-86 is closed too - all due to lake effect snow.
NWS Buffalo radar higher tilts show a boundary to the north of a strong lake band that’s not easily observed in the lowest tilt.
Mayor Jimmy Griffin from 1985 says 'stay home and grab a 6 pack' during a blizzard. Although not a blizzard, the subject of "6 Pack Jimmy' always pops up during major lake effect events.
NYDOT post stating a Thruway closure.
The first foot of snow (12.9 inches) east of Lake Erie. Cassadaga NY at 1PM, Nov 29, 2024.
The probability of at least 18" of snow for areas east of Lake Erie and Lake Ontario through 7PM Sunday.
NWS BUF ASOS reports snow on Nov 28, 2024.
Moderate impacts are over the same areas as "Minor Impacts", but with lower percentage values for now.