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davidzaff.bsky.social
Dave Zaff
@davidzaff.bsky.social
350 followers 420 following 170 posts
Meteorologist. I like snow, all kinds. Except blizzards. I don’t like blizzards.
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davidzaff.bsky.social
The NWS forecast Saturday morning was 50%.
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,
June 16, 2025 at 12:02 AM
davidzaff.bsky.social
Searching for NOAA in today’s news…
A search for ‘NOAA’ in today’s news turns up multiple troubling articles regarding cutback, along with other issues. A search for ‘NOAA’ in today’s news turns up multiple troubling articles regarding cutback, along with other issues.
May 8, 2025 at 4:58 PM
davidzaff.bsky.social
Nice little shelf cloud in Western NY this eve. 5/1/25 2249Z.
Shelf cloud above East Aurora NY. KBUF reflectivity and velocity.
May 1, 2025 at 10:54 PM
davidzaff.bsky.social
Mesoscale marine effects on Lake Erie.
April 30, 2025 at 6:46 PM
davidzaff.bsky.social
A rare Day 3 (Tuesday) convective outlook for Western NY and PA. (30-44% chance for severe weather within 25 mi.)

10% chance for significant severe weather, defined in alt text.
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.
April 27, 2025 at 8:27 PM
davidzaff.bsky.social
Oneida Lake is showing off it's lake shadow early this afternoon. Not bad for a little guy compared to Lake Ontario.
April 9, 2025 at 4:42 PM
davidzaff.bsky.social
Partial solar eclipse information for the Buffalo, NY area tomorrow, Mar 29, 2025:

05:29 AM: Partial eclipse begins (below horizon)
07:02 AM: Sunrise
07:05 AM: Maximum eclipse
07:09 AM: Partial eclipse ends

Hardly noticeable, and probably cloudy anyway.

www.timeanddate.com/eclipse/in/u...
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 image of the 00Z 3/28/25 HREF run valid at 11Z Saturday shows a high probability of low, mid, and high clouds over Buffalo, NY during the upcoming partial solar eclipse. https://www.spc.noaa.gov/exper/href/?model=href&product=cloudcover_mean&sector=ne
March 28, 2025 at 2:09 PM
davidzaff.bsky.social
Interesting "ice bridge" on Lake Erie between connecting Long Point, Ontario to PA and NY this afternoon as seen from the NOAA-21 polar orbiter this afternoon. I wouldn't cross it though.
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.
March 21, 2025 at 8:17 PM
davidzaff.bsky.social
Lake Erie ice, now down to 18% coverage is flowing nicely today.

apps.glerl.noaa.gov/coastwatch/w...

geosphere.ssec.wisc.edu#playing:true...;
March 18, 2025 at 6:08 PM
davidzaff.bsky.social
Bassfield MS. (Summary of PTDS from GR3)
PTDS showing the probability of the Tornado Detection Signature heading for Bassfield, MS at 107PM CDT (1807Z) 03/15/2025
March 15, 2025 at 6:19 PM
davidzaff.bsky.social
Lunar eclipse viewing looks pretty good for Western NY with mainly high thin clouds overnight.

Full eclipse begins: 06:26Z (2:26 am EDT)
Maximum Eclipse: 06:58Z (2:58 am EDT)
Full Eclipse ends: 07:31Z (3:31 am EDT)

www.spc.noaa.gov/exper/href/?...

www.timeanddate.com/eclipse/luna...
March 13, 2025 at 3:46 PM
davidzaff.bsky.social
Some nice hole punches over Western NY this morning. GOES-16 mesosector from 1219-1318Z March 3, 2025.
March 3, 2025 at 2:03 PM
davidzaff.bsky.social
Nice. I was in just about the same spot last spring. I didn't howl though.
Leprechaun Canyon
February 27, 2025 at 8:07 PM
davidzaff.bsky.social
Lake Erie ice cover is down to 81% today. SAR data shows some notable open areas east of Lake Erie Islands and north of Long Point.

www.star.nesdis.noaa.gov/socd/mecb/sa...
apps.glerl.noaa.gov/coastwatch/w...
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. Normalized Calibrated Radar Cross-section (NCRS), is a better tool to see ice cover. This image shows notable open water areas east of the Lake Erie Islands and north of Long Point.
February 26, 2025 at 6:13 PM
davidzaff.bsky.social
Like the classic quote in Princess Bride, “mostly dead is slightly alive”… Just because ‘Lake Erie is mostly ice covered’ doesn’t mean we can’t have lake effect snow.
A plume of lake effect snow can be found across Central Erie County, NY around 11:30 AM on February 19, 2025 Roads are quickly becoming snow covered within the snow band.
February 19, 2025 at 5:14 PM
davidzaff.bsky.social
Impressive! Ice cover over Lake Erie increased from around 27% on Sunday to near 80% on Wednesday. SAR NCRS does a spectacular job capturing this without cloud interference. #lakeerie

www.star.nesdis.noaa.gov/socd/mecb/sa...
apps.glerl.noaa.gov/coastwatch/w...
January 23, 2025 at 12:21 PM
davidzaff.bsky.social
Looks like I made it past the 100" mark this week for seasonal snow... 107.3" and counting. Here's my CoCoRaHS seasonal snow summary from 2008-today. It's not an official climatology, but it does roughly match local stats showing this location just above 100"/year.

www.weather.gov/media/erh/ta...
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 climatology of seasonal snow for Western NY, based on: https://www.weather.gov/media/erh/ta/ta2018-01.pdf
January 22, 2025 at 6:34 PM
davidzaff.bsky.social
Here's a dprog/Dt of the ECMWF's Extreme Forecast Index (EFI - shaded) and the Shift of Tails (SOT - black contours) for snowfall. Images start on Wed 00Z Jan 15, 2025, and continue at 24 hr time steps.
January 22, 2025 at 3:37 PM
davidzaff.bsky.social
It’s time for another dump! 2-4”/hr under an intense lake effect snowband east of Lake Erie.
January 22, 2025 at 12:26 AM
davidzaff.bsky.social
Lake Erie ice cover for 1/20/25: 38%. This morning's SAR products show increasing shore ice with more widespread ice building across the lake west of of a line from roughly Rondeau Park Ontario south to Cleveland OH.

apps.glerl.noaa.gov/coastwatch/w...
www.star.nesdis.noaa.gov/socd/mecb/sa...
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.
January 21, 2025 at 4:15 PM
davidzaff.bsky.social
Thundersnow! The strike over Lake Erie was about 17 miles away. Maybe I heard and saw the flash from another one? Oh, and it’s coming’ down hard!
Buffalo NY radar shows a strong single band lake effect snow event with a lightning overlay. A single strike is over Lake Erie.
January 21, 2025 at 1:57 AM
davidzaff.bsky.social
Atlanta, GA: ‘It might snow again next Wednesday!’

Western NY: ‘That’s nice.’
Forecast for Atlanta, GA Forecast for Western NY
January 18, 2025 at 12:59 PM
davidzaff.bsky.social
SAR products had some great passes over Lake Erie this morning, offering a nearly complete picture of ice. The NCRS does a better job with ice detail, but colorized wind speed, with GFS wind barbs, also shows ice, albeit with erroneous wind speeds.

www.star.nesdis.noaa.gov/socd/mecb/sa...
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. SAR-derived wind speed products can show ice cover as well, but with erroneous speeds as the product is designed for open water.
January 17, 2025 at 5:22 PM
davidzaff.bsky.social
Challenging lake effect snow forecasts next week east of Lake Erie. Ice coverage on 1/16/2025: 35% (mostly west side). Forecasts show a rapid increase as arctic blast moves in. There is a potential for a strong lake effect response with below zero wind chill, but it'll be a battle as ice increases.
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. The NAEFS mean 500mb heights from the Jan 17, 2025 00Z run valid 12Z Tues Jan 21, 2025 shows a shortwave trough over the western Great Lakes rounding the base of a long wave trough over much of the Northeast US and Canada, with a longwave ridge over the West. This pattern is favorable for a lake effect response.
January 17, 2025 at 1:18 PM
davidzaff.bsky.social
Palisades Fire CA via GOES-18. #PalisadesFire

col.st/j2Xaq
January 7, 2025 at 8:29 PM