Saturday, November 17, 2018

Winter '18 / '19 - Snow Storm #1: Preliminary STP Verification

Table of preliminary storm-total snowfall by station for THU and FRI from CDUS41 (CLI) ... CXUS51 (CF6) and ... SAUS41 (METAR) bulletins.

Exceptions:
BDR - daily snowfall reports missing.
STP estimated from METAR 6/nnnn group @ SLR 10:1

SLR not reported for some stations with measurable snowfall b/c liquid and / or freezing precipitation also occurred during the verification period.

---
Stations observing at least Trace - 20 (74%)

Given a forecast station observed measurable snowfall ... stations observing at least:
4" - 10 (50%)
6" - 5 (30%)
8" - 3 (15%)
10" - 0

Max snow melt-water
CAR - 0.70"
BTV - 0.62"
CON - 0.60"
JFK - 0.91"

BGM SLR 6:1 (no liquid precipitation reported)

Max precipitation:  ACY - 1.73"

---
New daily records:
15-NOV-18 (1)
ORH - 7.8" (5.7"; 1967)

Eleven daily records set this day -- some held since 1906; however ... snow fell on ten stations before the deadline; therefore  ... they are not included.

16-NOV-18 (4)
CAR - 9.3" (5.4"; 1973)
BGM - 4" (1.8"; 1987, 1999)
ABE - 0.7" (0.05"; 1995)
MDT - 0.5" (0.05"; 1985)


SFC analysis:  00z ... 16-NOV-18

---
Please report errors in Comments along with a link to the correct data.
FINAL Results post expected SUN evening ... 18-NOV-18

11 comments:

Anonymous said...

Verification looks great except for the following stations which hourly obs indicate the following:

PWM 8"

BOS 4"

BDR 4"

ISP 4"

Anonymous said...

Correction:

PWM is ok

but BGR had over 10 hours of snow

Anonymous said...

BGR 6"

2" on the 17th

4" on the 16th

https://www.nohrsc.noaa.gov/nearest/index.html?city=Bangor%2C+ME&county=&l=5&u=e&y=2018&m=11&d=16

https://www.nohrsc.noaa.gov/nearest/index.html?city=Bangor%2C+ME&county=&l=5&u=e&y=2018&m=11&d=17



TQ said...

will check on the stations listed above; however ... remember only snowfall observed after 8 PM on THU counts.

TQ said...

Anon wrote:
BGR 6"
2" on the 17th

---
The 2" on the 17th occurred outside the verification period.
Verification period ended FRI ... 16-NOV-18 @ 11:59 pm

TQ said...

Anon wrtote
BOS 4"

---
F6 bulletin carries 0.1" on the 15th. METARs indicate it fell during the verification period.


F6 bulletin carries T on the 16th
https://forecast.weather.gov/product.php?site=NWS&product=CF6&issuedby=bos

... as does the CLI
https://forecast.weather.gov/product.php?site=NWS&product=CF6&issuedby=bos

Do you have a link to support 4" @ BOS?

TQ said...

Anon wrtote:
BDR 4"
ISP 4"

---
BDR SN changed to UP @ 9:15 pm then FZRA.
METARS between 8 and 9:15pm suggest 1" at best.

ISP only T after 8 pm from ice pellets (PE).
METARs indicate PE ended @ 8:36 pm.

Anonymous said...

Boston

from the hourlies:

https://w1.weather.gov/data/obhistory/KBOS.html

11/15 (all "light snow"

20:54 .09

21:54 .09

22:54 .12

23:54 .14



TQ said...

The period of light snow between 8 pm and midnight on the 15th is reflected in the CLI / F6 reports as 0.1". The accumulation was so low b/c the air temperature was several degrees above freezing.

TQ said...

thx Anon for looking at the data. second set of eyes is always good.

Anonymous said...


https://www.wgbh.org/news/2017/07/19/science-and-technology/why-bostons-official-weather-measured-logan-airport

https://www.weather.gov/jetstream/asos