Weather Forecasts (Chesapeake in this case) - SailNet Community
 1Likes
Reply
 
LinkBack Thread Tools
post #1 of 14 Old 05-13-2013 Thread Starter
Junior Member
 
EuroboyDC's Avatar
 
Join Date: May 2013
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Weather Forecasts (Chesapeake in this case)

Good morning!

I am taking the boat out of Herrington Harbour North this afternoon and am a little bit perplexed by the forecast(s). I'm wondering if anyone could shed some light on this, as I always try to keep an eye on the weather.

- NWS says there is a small craft advisory in effect through late tonight from Sandy Point to North Beach. To my recollection, an SMA is triggered between 22-33 knot winds.

For this afternoon:

- Weather.com for Deale, MD, says 11-13 mph (9-11 knots) winds
- Windguru says 8-7 knots/gusting 11-13 knots (GFS), and 10-12 knots/gusting 13-14 knots (NAM). HRWe simply says 12-16 knots.
- Passageweather.com indicates 10 knots, dying off to 5 knots by 5pm.

As you can see, there is a good degree of contradiction here. Which model should I trust?

Also, given the circumstances, would you go out with a reef on a 30' O'Day 302 or just go full canvas?

Thanks for any insight!

Nico

Last edited by EuroboyDC; 05-13-2013 at 10:57 AM.
EuroboyDC is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 14 Old 05-13-2013
美国华人, 帆船 教授及输送
 
Join Date: Sep 2006
Location: MD
Posts: 2,531
Thanks: 24
Thanked 23 Times in 15 Posts
Rep Power: 9
 
Re: Weather Forecasts (Chesapeake in this case)

For local sailing in the Bay, I always rely on NOAA and the weather channel on VHF.

Depending on your skills and the familiarity of the boat, to stay on the safe side, just reef. Besides, it is early in the season, just take it easy for a while.

Have fun !!!

PS: Welcome to Sailnet


Fine Print:
I am old school. Integrity is to do the right thing even when no one is watching.
rockDAWG is offline  
Quote Quick Reply Share with Facebook
post #3 of 14 Old 05-13-2013
Senior Member
 
jsaronson's Avatar
 
Join Date: Dec 2011
Posts: 997
Thanks: 5
Thanked 31 Times in 31 Posts
Rep Power: 4
 
Re: Weather Forecasts (Chesapeake in this case)

I start with the hourly forecast:
Hourly Weather Forecast for 38.97N 76.49W

I also check Thomas Point:
NDBC - Station TPLM2

It is usually easier to shake out a reef than put one in.
jsaronson is offline  
Quote Quick Reply Share with Facebook
post #4 of 14 Old 05-13-2013 Thread Starter
Junior Member
 
EuroboyDC's Avatar
 
Join Date: May 2013
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Weather Forecasts (Chesapeake in this case)

Thank you for your feedback, gents.

I suppose I was mostly curious about the forecasts when seeing the SCA - it just doesn't make much sense to me, unless NWS is being overly conservative in issuing them.

But as you suggest, I'll probably start out with a reef as I can always shake it out if it's not needed.

Cheers!

Nico
EuroboyDC is offline  
Quote Quick Reply Share with Facebook
post #5 of 14 Old 05-13-2013
Dragon Mod
 
DRFerron's Avatar
 
Join Date: Nov 2005
Location: SE Pennsylvania
Posts: 4,726
Thanks: 110
Thanked 212 Times in 194 Posts
Rep Power: 10
 
Dock
Re: Weather Forecasts (Chesapeake in this case)

Nico,

Small craft advisory numbers are localized. So may be one thing outside of the Chesapeake, they may not be the same in the Chesapeake area. Each local NWS station around the country determines what they consider the wind speed/wave height combination should be for a SCA in their specific area.

At least, that's what was told to us at the weather seminar I took with a NWS forecaster.

Donna


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Catalina 30 TRBS
DRFerron is offline  
Quote Quick Reply Share with Facebook
post #6 of 14 Old 05-13-2013
Senior Smart Aleck
 
jameswilson29's Avatar
 
Join Date: Aug 2009
Location: Richmond, Virginia
Posts: 2,152
Thanks: 34
Thanked 70 Times in 65 Posts
Rep Power: 7
 
Re: Weather Forecasts (Chesapeake in this case)

Quote:
Originally Posted by EuroboyDC View Post
- NWS says there is a small craft advisory in effect through late tonight from Sandy Point to North Beach. To my recollection, an SMA is triggered between 22-33 knot winds...
As you can see, there is a good degree of contradiction here. Which model should I trust?
There is no contradiction. The NOAA weather radio Small Craft Advisory is issued in advance of the SCA conditions and does not necessarily reflect current conditions. The weather synopsis portion of the forecast informs us that high pressure is steadily moving into this area through tonight. The wind speed range is predicted to increase another 5 knots this afternoon and evening from 10-15 knots to 15 to 20 knots - that is the basis for the SCA.

Quote:
Originally Posted by EuroboyDC View Post
Also, given the circumstances, would you go out with a reef on a 30' O'Day 302 or just go full canvas?
I would not head out with a reef in the main in those conditions, but I would be more conservative in my jib choice with predicted increase in wind speed.

I head out plannng to use a full main, usually, then I judge the headsail by the conditions. You can always ease the main to reef once the jib is up. I usually rig everything in the marina for ease of possible use: jib sheets, whisker pole, spinnaker pole, spin sheets, turning blocks, unless I am only going for a short sail. On a number of occasions, it gets stowed without being used that day.

Last edited by jameswilson29; 05-13-2013 at 12:17 PM.
jameswilson29 is offline  
Quote Quick Reply Share with Facebook
post #7 of 14 Old 05-13-2013
Senior Member
 
pdqaltair's Avatar
 
Join Date: Nov 2008
Location: Deale, MD
Posts: 2,601
Thanks: 1
Thanked 53 Times in 53 Posts
Rep Power: 7
 
Re: Weather Forecasts (Chesapeake in this case)

The definition of SCA depends on the area (google it). On the Chesapeake and Potomac it is :

Small Craft Advisory

Small Craft Advisories are issued for the Tidal Potomac River and the Chesapeake Bay when one or both of the following conditions is expected to begin within 36 hours:

1) sustained winds of 18 knots to 33 knots

OR

2) frequent gusts (duration of two or more hours) between 18 knots and 33 knots.

OR

3) waves of 4 feet or higher


Second, you really need to use NOAA wind speeds. Yes, this was a minimal SCA. Additionally, your feeling on the subject might be different at the mouth of the Potomac in a sailing dingy with a green crew. It is just an advisory. For cruising boats it mostly means clear the table, just in case.

(when asked how he reached the starting holds on a difficult rock climbing problem that clearly favored taller climbers - he was perhaps 5'5")

"Well, I just climb up to them."

by Joe Brown, English rock climber




To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
pdqaltair is offline  
Quote Quick Reply Share with Facebook
post #8 of 14 Old 05-13-2013
Senior Smart Aleck
 
jameswilson29's Avatar
 
Join Date: Aug 2009
Location: Richmond, Virginia
Posts: 2,152
Thanks: 34
Thanked 70 Times in 65 Posts
Rep Power: 7
 
Re: Weather Forecasts (Chesapeake in this case)

Good point. Here are two very different examples of SCA, both near the mouth of the Potomac, one gusting and one with waves:

Gusting from the South (small waves near southern shore of Potomac):

Waves from a prolonged North wind, fairly stead wind in the teens:

Last edited by jameswilson29; 05-13-2013 at 12:26 PM.
jameswilson29 is offline  
Quote Quick Reply Share with Facebook
post #9 of 14 Old 05-13-2013
Senior Member
 
chef2sail's Avatar
 
Join Date: Nov 2007
Location: Maryland
Posts: 7,096
Thanks: 30
Thanked 58 Times in 54 Posts
Rep Power: 8
 
Send a message via AIM to chef2sail
Re: Weather Forecasts (Chesapeake in this case)

I have found that Lat-36.com to be most accurate for wind/ weather forcasting. Uses a variety of data


http://l-36.com/weather.php?lat=38.9...=ANZ500&v=0.50
Jiminri likes this.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
___________________________
S/V Haleakala (Hawaiian for" House of the Sun")
C&C 35 MKIII Hull # 76
Parkville, Maryland
(photos by Joe McCary)
Charter member of the Chesapeake Lion posse

Our blog-
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


“Sailing is just the bottom line, like adding up the score in bridge. My real interest is in the tremendous game of life.”- Dennis Conner
chef2sail is offline  
Quote Quick Reply Share with Facebook
post #10 of 14 Old 05-13-2013 Thread Starter
Junior Member
 
EuroboyDC's Avatar
 
Join Date: May 2013
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Weather Forecasts (Chesapeake in this case)

Thank you all for the additional feedback and info. As for the localized SCA parameters - I learned something new again. I do Google just about everything, but this didn't pop up.

Three hours to sailtime now, so we'll see how it goes. I do like the idea of putting up the full main and gauging the jib. Thankfully, I can just furl/unfurl the genny as needed. It'll help to have crew onboard this time, too. I took out a Catalina 27 on Cinco de Mayo, and that was a bit of a pain to single-hand that day.

For what it's worth, I'll post how it went afterwards - assuming I remember to do so, as the post-sail activities will involve watching the Caps in Game 7 at Calypso. (Sorry, Rangers fans)

Thanks again!

Nico
EuroboyDC is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Weather Forecasts for Sailors Michael Carr Seamanship Articles 0 08-31-1998 08:00 PM
Marine VHF Weather Forecasts Michael Carr Learning to Sail Articles 0 04-30-1997 08:00 PM
Marine VHF Weather Forecasts Michael Carr Seamanship Articles 0 04-30-1997 08:00 PM
Marine VHF Weather Forecasts Michael Carr Gear and Maintenance Articles 0 04-30-1997 08:00 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome