Sign In Become a Member
Donate
Daily Discussions

Saturday, May 10, 2025

May 10, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SATURDAY, MAY 10, 2025 ALL TIMES ARE…

Agreement required — click “Accept & Continue” below to review and accept the Data Use & Privacy Policy

Access to this content requires acceptance of our Data Use & Privacy Policy.

BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

SATURDAY, MAY 10, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0428E
SUNSET:  1854E

DRIZZLE AND FOG LINGER AS STORM DEPARTS….

The storm system that has been impacting us since yesterday afternoon
has dropped beneficial rainfall, with a storm total so far of 1.42″.
The steady rain came to an end before midnight, with a thunderstorm
mid-morning followed by drizzle and light rain thereafter.

Temperatures are slowly climbing, beginning the day in the mid 40s and
now reaching the low 50s. Like yesterday, this is below normal for the
time of year.

The wind began out of the east-northeast early this morning. Since then,
the direction has shifted, and is now out of the west-northwest as the storm
heads offshore. Speeds have been steady, with an average thus far of 11mph.
The peak gust is not too impressive, being 25mph just after 12:30pm.

Visibility remains poor due to low clouds and fog, holding in the 2-3
mile range.

The maximum temperature for today is 53F degrees, which is 12 degrees
below the normal high of 65F. The minimum temperature since midnight
is 45F degrees, which is 2 degrees below the normal low of 47F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 200ft, fog
Temperature: 45F; Dew Point: 45F; Relative Humidity: 100%
Wind: NNW @ 10G15 kts
Sea-level pressure: 1006.8 mb; 29.73 in. Hg: steady, then falling
Visibility: 3 miles, fog
6-hr Max temp: 47F
6-hr Min temp: 45F
24-hr Precip:  1.36 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 X W2 3F 068/45/45/3410G15/973/ 8//// 58008 70136 10047 20045

10 A.M.
Weather: Sky obscured, vertical visibility 200ft, light drizzle and fog
Temperature: 49F; Dew Point: 49F; Relative Humidity: 100%
Wind: NW @ 10G17 kts
Sea-level pressure: 1008.1 mb; 29.77 in. Hg: steady, then rising
Visibility: 2 miles, fog
3-hr Precip:  0.03 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 X W2 2L-F 081/49/49/3210G17/977/ 8//// 53013 6003/

1 P.M.
Weather: Broken stratus fractus, overcast nimbostratus,
light drizzle and fog
Temperature: 53F Dew Point: 53F; Relative Humidity: 97%
Wind: WNW @ 11G19 kts
Sea-level pressure: 1010.0 mb; 29.83 in. Hg: rising unsteadily
Visibility: 3 miles, fog
6-hr Max temp: 53F
6-hr Min temp: 45F
6-hr Precip:  0.06 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E5 BKN 35 OVC 3L-F 010/53/53/3011G19/983/ 8/72/ 52019
6006/ 10053 20045

————————————————————–

SUMMARY FOR FRIDAY, MAY 9, 2025

TEMPERATURE (DEGREES F)
MAX…….51   NORMAL…..65
MIN…….46   NORMAL…..46
MEAN……49   NORMAL…..56

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-7
TOTAL DEPARTURE FOR THE MONTH………………………+39 [+4.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….16  DEPARTURE……..+6
TOTAL HEATING UNITS FOR THE MONTH…………….59  DEPARTURE…….-39
TOTAL HEATING UNITS FOR THE SEASON………….5457  DEPARTURE……-528
TOTAL HEATING UNITS LAST SEASON TO DATE……..5253  DEPARTURE……+204

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH……………..4  DEPARTURE………0
TOTAL COOLING UNITS FOR THE SEASON…………….7  DEPARTURE………0
TOTAL COOLING UNITS LAST SEASON TO DATE………..2  DEPARTURE……..+5

PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all on Main Tower.
E=Estimated

F420C (Official)………..33 E    @   05:26 P.M.
VECTOR #1 (1-Sec)……….34 ENE  @   05:46 P.M.
VECTOR #2 (1-Sec)……….34 ENE  @   05:45 P.M.
DAVIS #1……………….33 E    @   05:25 P.M.
DAVIS #2 ………………33 E    @   05:46 P.M.
RMY #1 (Instantaneous)…..35 ENE  @   05:33 P.M.
RMY #2 (Instantaneous)…..35 ENE  @   02:17 P.M.
MERLIN…………………32 ENE
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………25 ENE  @   05:30 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..21      @   11:23 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..26      @   05:47 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………26 E    @   05:27 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………26 E    @   05:47 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..24 E    @   05:29 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..25 ENE  @   05:47 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..13.3 ENE [319 total miles] VECTOR #1………………12.2
VECTOR #2………………13.4
DAVIS #1……………….13.7 ENE
DAVIS #2……………….13.6 E
RMY #1…………………12.5 ENE
RMY #2…………………13.1 ENE
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..1.36 DEPARTURE…..+1.25
TOTAL PRECIPITATION FOR THE MONTH…………..2.64 DEPARTURE…..+1.53
TOTAL PRECIPITATION FOR THE YEAR (2025)…….16.76 DEPARTURE…..-3.13

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE…….0.0
TOTAL SNOWFALL FOR THE MONTH………………..0.0 DEPARTURE…….0.0
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……35.8 DEPARTURE…..-33.9

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
PEAK GUST: F420C (Official)
VEC1: Vector #1 1-second gust
RMY:  R.M. Young #1 wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M:    Missing data

5/1   69/43/56/+3/0.00/0.0/744/88        28 S   VEC1 28 SSW RMY 28
5/2   79/47/63/+9/0.19/0.0/339/40        28 SE  VEC1 29 SE  RMY 25 TSTM
5/3   84/54/69/+15/0.15/0.0/561/66       43 SSW VEC1 42 SSW RMY 44 TSTM
5/4   77/50/64/+10/0.06/0.0/256/30       33 SW  VEC1 34 SW  RMY 32
5/5   50/46/48/-7/0.26/0.0/000/00        35 ENE VEC1 35 ENE RMY 36
5/6   61/48/55/0/0.57/0.0/000/00         26 S   VEC1 27 ENE RMY 27
5/7   72/54/63/+8/0.01/0.0/310/36        33 SSW VEC1 33 SW  RMY 35
5/8   74/51/63/+8/0.04/0.0/…/..        18 ESE VEC1 18 ESE RMY 18
5/9   51/46/49/-7/…./0.0/…/..        33 E   VEC1 34 ENE RMY 35

5/10 The low since midnight is 45F, the daily normal low is 47F.

————————————————————–

MAY DAILY RECORDS TO DATE

NONE.

————————————————————–

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)

RECORDS FOR MAY 10
HIGH 93F IN 1896
LOW 29F  IN 1900
PRECIP 1.85 INS IN 1998
SNOW 2.8 INS 1977 (7.8 INS TOTAL 5/9-5/10 1977)
PEAK GUST 64 MPH S IN 1990

RECORDS FOR MAY 11
HIGH 90F IN 1993
LOW 28F IN 1900
PRECIP 1.28 INS IN 1957
SNOW 1.0 INS IN 1907 (LATEST MEASURABLE SNOW ON RECORD)
PEAK GUST 75e MPH NW IN 1945

TODAY’S REPORT PREPARED BY: Joshua Polen

facebookShare on Facebook
TwitterPost on X
FollowFollow us
PinterestSave
←
→
Blue Hill Observatory & Science Center · Legal

Data Use & Privacy Policy

Please read the full Policy before accessing Observatory data · Effective January 1, 2025

Notice: By accessing, downloading, or using any Blue Hill Observatory data or services, you unconditionally accept and agree to be bound by this Policy in its entirety. If you do not agree, you may not access or use Observatory data.
Effective January 1, 2025 · Milton, Massachusetts · bluehill.org
Part I — Data Use Policy
§ 01

Ownership and Proprietary Rights

All observational records, compiled datasets, metadata, database structures, and related materials provided by the Blue Hill Observatory & Science Center are the exclusive property of the Blue Hill Observatory & Science Center. The Observatory has maintained continuous weather observations at the summit of Great Blue Hill since 1885, and the entirety of that record — its compilation, structure, curation, and organization — constitutes a proprietary database protected under applicable United States law, including copyright law and common law database protections.

All rights not expressly granted in this Policy are reserved by the Observatory. No access to or use of Observatory data shall be construed as a waiver of any rights or as a license to use data beyond the scope expressly stated herein.

§ 02

Governing Law and Jurisdiction

This Policy shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without regard to its conflict of law provisions. For interactions with international users, this Policy shall apply to the maximum extent permitted by applicable local law.

Any dispute arising from or related to this Policy shall be subject to the exclusive jurisdiction of the state and federal courts located in Norfolk County, Massachusetts. By accessing Observatory data, all users consent to personal jurisdiction in Massachusetts and waive any objection to the venue or inconvenience of such forum.

§ 03

Permitted Uses

Observatory data are made available for the following limited, non-commercial purposes only:

  • Personal study and analysis
  • Educational classroom use
  • Student projects
  • Non-commercial academic research
  • Publication of analyses, figures, models, or conclusions derived from the data, subject to the attribution requirements of Section 4

All other uses require prior written authorization from the Observatory.

§ 04

Attribution Requirement

Any use of Observatory data in any published, presented, or publicly distributed work must include the following verbatim acknowledgment:

“Data provided by the Blue Hill Observatory & Science Center, Milton, Massachusetts. Continuous weather observations since 1885.”

Failure to include proper attribution is a material violation of this Policy.

§ 05

Prohibited Uses

Unless explicitly authorized in writing, Users may not:

  • Resell, license, sublicense, or commercially exploit Observatory data in any form
  • Redistribute the dataset in whole or in part to any third party
  • Publish the dataset for download by third parties
  • Host, mirror, or archive the dataset on any external website, repository, or storage service
  • Upload the dataset to any public or institutional data repository
  • Provide the data through APIs, automated services, or subscription platforms
  • Incorporate the data into any commercial product, software, application, or service
  • Use the data for AI or machine learning systems intended for commercial use or external distribution
  • Use the data to create derivative datasets that enable reconstruction of the underlying observations
§ 06

Commercial Licensing

Organizations seeking to use Observatory data for commercial purposes must obtain a license prior to any such use. Licensing inquiries: data@bluehill.org.

§ 07

Automated Access

Automated scraping, bulk harvesting, or systematic downloading of Observatory data is strictly prohibited without prior written authorization.

§ 08

Enforcement and Remedies

Violation of this Policy may result in immediate revocation of data access, pursuit of legal remedies available under United States law, and referral to applicable authorities. The Observatory reserves all rights to seek injunctive relief, damages, and attorneys’ fees in connection with any unauthorized use of its data.

Part II — Privacy Policy
§ 09–10

Scope & Information Collected

This section governs the collection, use, storage, and disclosure of personal information from visitors to the Blue Hill Observatory website and users of its data services. The Observatory may collect contact information (name, email, organization) when voluntarily submitted, usage data including IP addresses and pages visited, and data download records.

§ 11–12

How We Use Information & Retention

Information is used solely for: responding to inquiries and licensing requests; monitoring and enforcing compliance with this Policy; improving website performance; and communicating Observatory news to opted-in users. The Observatory does not sell, rent, or share personal information with third parties for marketing purposes. Data access records may be retained indefinitely for compliance and enforcement purposes.

§ 13

International Users and Data Transfers

The Observatory is located in the United States. International users acknowledge their information will be processed in the United States under U.S. law. Users requiring specific data processing agreements under non-US law must contact data@bluehill.org before accessing data.

§ 14–16

Cookies, Security & Children’s Privacy

The Observatory website may use cookies for analytics and functionality. By continuing to use the site, users consent to cookie use. The Observatory implements reasonable measures to protect personal information but cannot guarantee absolute security. Observatory data services are not directed at children under 13.

Part III — General Provisions
§ 17–20

Modifications, Severability, Entire Agreement & Contact

The Observatory reserves the right to modify this Policy at any time. Updated versions will be posted at bluehill.org. Continued use of Observatory data following any modification constitutes acceptance of the revised Policy. This Policy constitutes the entire agreement between the User and the Observatory. Questions and licensing inquiries: Blue Hill Observatory & Science Center, Milton, Massachusetts — data@bluehill.org

By accessing, downloading, or using any Blue Hill Observatory data or services, you acknowledge that you have read, understood, and agree to be bound by this Policy.
Effective January 1, 2025 · Blue Hill Observatory & Science Center · Milton, Massachusetts
↓ Scroll to read the full Policy — the agreement checkbox will unlock at the bottom
Main Menu