weather prediction and HR

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brianvh
Posts: 1437
Joined: Wed Feb 09, 2005 2:32 pm
Location: manhattan, New York

weather prediction and HR

Post by brianvh »

Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
predicted to be 5-10 and no snow reminds me of something I just saw in my
statistics for meteorology class I saw yesterday.

Some background: numerical weather models do best for upper air
predictions - near the surface some statistical fitting is done on models
versus observation history so that given the model predictions, you can
predict the surface conditions. The result is called Model Output
Statistics or "MOS". To get enough data for statistics they break the
country up into separate regions and apply uniform statistics throughout
each region. The text forecasts are usually based on MOS.

We had the lead MOS guy from NOAA in talking about what they do. He
showed a map of the different regions, and one of the borders follows the
MD-PA line.

Gee...guess where High Rock is? I would suppose if you average the HR and
Pulpit text forecasts you may get a good approximation to the correct HR
forecast. Or maybe the HR forecast will be closer to the Pulpit forecast
due to being on the Pulpit side of the mountain range. Anyone noticed
long term trends to back this up?

Brian Vant-Hull
301-646-1149
dbodner
Posts: 882
Joined: Tue Jan 18, 2005 11:24 pm
Location: Arlington

weather prediction and HR

Post by dbodner »

I don't have much historical perspective, but I've been noticing on the
USWS Graphical Forecast
(http://weather.gov/forecasts/graphical/sectors/
marylandWeek.php?page=2&element=T) the predicted wind direction shifts
noticeably across the Mason-Dixon line. I was wondering why a
political boundary would affect air molecules so much.

On Friday, March 11, 2005, at 04:57 PM, Vant-Hull - Brian wrote:

>
>
> Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> predicted to be 5-10 and no snow reminds me of something I just saw in
> my
> statistics for meteorology class I saw yesterday.
>
> Some background: numerical weather models do best for upper air
> predictions - near the surface some statistical fitting is done on
> models
> versus observation history so that given the model predictions, you can
> predict the surface conditions. The result is called Model Output
> Statistics or "MOS". To get enough data for statistics they break the
> country up into separate regions and apply uniform statistics
> throughout
> each region. The text forecasts are usually based on MOS.
>
> We had the lead MOS guy from NOAA in talking about what they do. He
> showed a map of the different regions, and one of the borders follows
> the
> MD-PA line.
>
> Gee...guess where High Rock is? I would suppose if you average the HR
> and
> Pulpit text forecasts you may get a good approximation to the correct
> HR
> forecast. Or maybe the HR forecast will be closer to the Pulpit
> forecast
> due to being on the Pulpit side of the mountain range. Anyone noticed
> long term trends to back this up?
>
> Brian Vant-Hull
> 301-646-1149
>
>
Flying Lobster
Posts: 1042
Joined: Fri Feb 25, 2005 4:17 pm

the answer

Post by Flying Lobster »

I have an answer for this very question--but due to legal reasons you will have to go to the general discussions forum to see it.

Marc
Great Googly-moo!
User avatar
TQ
Posts: 42
Joined: Thu Feb 10, 2005 5:34 pm
Location: KPTB
Contact:

weather prediction and HR

Post by TQ »

The reason why?

North (south) of the M-D, zone forecasts are issued by State College
(Sterling) NWS.

Zone forecasts are not MOS forecasts.

-----Original Message-----
From: David Bodner [mailto:d.bodner@verizon.net]
Sent: Friday, March 11, 2005 07:17 p.m.
To: hg_forum@chgpa.org
Subject: Re: weather prediction and HR


I don't have much historical perspective, but I've been noticing on the
USWS Graphical Forecast
(http://weather.gov/forecasts/graphical/sectors/
marylandWeek.php?page=2&element=T) the predicted wind direction shifts
noticeably across the Mason-Dixon line. I was wondering why a
political boundary would affect air molecules so much.

On Friday, March 11, 2005, at 04:57 PM, Vant-Hull - Brian wrote:

>
>
> Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> predicted to be 5-10 and no snow reminds me of something I just saw in
> my
> statistics for meteorology class I saw yesterday.
>
> Some background: numerical weather models do best for upper air
> predictions - near the surface some statistical fitting is done on
> models
> versus observation history so that given the model predictions, you can
> predict the surface conditions. The result is called Model Output
> Statistics or "MOS". To get enough data for statistics they break the
> country up into separate regions and apply uniform statistics
> throughout
> each region. The text forecasts are usually based on MOS.
>
> We had the lead MOS guy from NOAA in talking about what they do. He
> showed a map of the different regions, and one of the borders follows
> the
> MD-PA line.
>
> Gee...guess where High Rock is? I would suppose if you average the HR
> and
> Pulpit text forecasts you may get a good approximation to the correct
> HR
> forecast. Or maybe the HR forecast will be closer to the Pulpit
> forecast
> due to being on the Pulpit side of the mountain range. Anyone noticed
> long term trends to back this up?
>
> Brian Vant-Hull
> 301-646-1149
>
>
User avatar
TQ
Posts: 42
Joined: Thu Feb 10, 2005 5:34 pm
Location: KPTB
Contact:

weather prediction and HR

Post by TQ »

I am curious to know where the disparate forecasts are posted.

-----Original Message-----
From: Vant-Hull - Brian [mailto:brianvh@umd5.umd.edu]
Sent: Friday, March 11, 2005 04:58 p.m.
To: hg_forum@chgpa.org
Subject: weather prediction and HR



Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
predicted to be 5-10 and no snow reminds me of something I just saw in my
statistics for meteorology class I saw yesterday.
brianvh
Posts: 1437
Joined: Wed Feb 09, 2005 2:32 pm
Location: manhattan, New York

weather prediction and HR

Post by brianvh »

wouldn't much of the issued zone forecast surface variables be heavily
based on MOS?

Brian Vant-Hull
301-646-1149

On Fri, 11 Mar 2005, ToweringQs wrote:

>
> The reason why?
>
> North (south) of the M-D, zone forecasts are issued by State College
> (Sterling) NWS.
>
> Zone forecasts are not MOS forecasts.
>
> -----Original Message-----
> From: David Bodner [mailto:d.bodner@verizon.net]
> Sent: Friday, March 11, 2005 07:17 p.m.
> To: hg_forum@chgpa.org
> Subject: Re: weather prediction and HR
>
>
> I don't have much historical perspective, but I've been noticing on the
> USWS Graphical Forecast
> (http://weather.gov/forecasts/graphical/sectors/
> marylandWeek.php?page=2&element=T) the predicted wind direction shifts
> noticeably across the Mason-Dixon line. I was wondering why a
> political boundary would affect air molecules so much.
>
> On Friday, March 11, 2005, at 04:57 PM, Vant-Hull - Brian wrote:
>
> >
> >
> > Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> > predicted to be 5-10 and no snow reminds me of something I just saw in
> > my
> > statistics for meteorology class I saw yesterday.
> >
> > Some background: numerical weather models do best for upper air
> > predictions - near the surface some statistical fitting is done on
> > models
> > versus observation history so that given the model predictions, you can
> > predict the surface conditions. The result is called Model Output
> > Statistics or "MOS". To get enough data for statistics they break the
> > country up into separate regions and apply uniform statistics
> > throughout
> > each region. The text forecasts are usually based on MOS.
> >
> > We had the lead MOS guy from NOAA in talking about what they do. He
> > showed a map of the different regions, and one of the borders follows
> > the
> > MD-PA line.
> >
> > Gee...guess where High Rock is? I would suppose if you average the HR
> > and
> > Pulpit text forecasts you may get a good approximation to the correct
> > HR
> > forecast. Or maybe the HR forecast will be closer to the Pulpit
> > forecast
> > due to being on the Pulpit side of the mountain range. Anyone noticed
> > long term trends to back this up?
> >
> > Brian Vant-Hull
> > 301-646-1149
> >
> >
>
>
>
>
>
brianvh
Posts: 1437
Joined: Wed Feb 09, 2005 2:32 pm
Location: manhattan, New York

weather prediction and HR

Post by brianvh »

Yesterday's NWS text forecast. I just got them straight from the chgpa
webpage HR and pulpit links.

Brian Vant-Hull
301-646-1149

On Fri, 11 Mar 2005, ToweringQs wrote:

>
> I am curious to know where the disparate forecasts are posted.
>
> -----Original Message-----
> From: Vant-Hull - Brian [mailto:brianvh@umd5.umd.edu]
> Sent: Friday, March 11, 2005 04:58 p.m.
> To: hg_forum@chgpa.org
> Subject: weather prediction and HR
>
>
>
> Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> predicted to be 5-10 and no snow reminds me of something I just saw in my
> statistics for meteorology class I saw yesterday.
>
>
>
>
>
User avatar
TQ
Posts: 42
Joined: Thu Feb 10, 2005 5:34 pm
Location: KPTB
Contact:

weather prediction and HR

Post by TQ »

Maybe, maybe not.

NWS forecasts are now created through a gridded digital database, which can
be initialized with MOS from NGM, NAM (nee Eta), GFS (nee AVN), or LAMP
(local area MOS). Or, the database can be initialized with raw model output
from any of the models. Once initialized, the forecaster can adjust the
grids to reflect the forecaster/s subjective opinions.

-----Original Message-----
From: Vant-Hull - Brian [mailto:brianvh@umd5.umd.edu]
Sent: Saturday, March 12, 2005 08:34 a.m.
To: hg_forum@chgpa.org
Subject: RE: weather prediction and HR



wouldn't much of the issued zone forecast surface variables be heavily
based on MOS?

Brian Vant-Hull
301-646-1149

On Fri, 11 Mar 2005, ToweringQs wrote:

>
> The reason why?
>
> North (south) of the M-D, zone forecasts are issued by State College
> (Sterling) NWS.
>
> Zone forecasts are not MOS forecasts.
>
> -----Original Message-----
> From: David Bodner [mailto:d.bodner@verizon.net]
> Sent: Friday, March 11, 2005 07:17 p.m.
> To: hg_forum@chgpa.org
> Subject: Re: weather prediction and HR
>
>
> I don't have much historical perspective, but I've been noticing on the
> USWS Graphical Forecast
> (http://weather.gov/forecasts/graphical/sectors/
> marylandWeek.php?page=2&element=T) the predicted wind direction shifts
> noticeably across the Mason-Dixon line. I was wondering why a
> political boundary would affect air molecules so much.
>
> On Friday, March 11, 2005, at 04:57 PM, Vant-Hull - Brian wrote:
>
> >
> >
> > Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> > predicted to be 5-10 and no snow reminds me of something I just saw in
> > my
> > statistics for meteorology class I saw yesterday.
> >
> > Some background: numerical weather models do best for upper air
> > predictions - near the surface some statistical fitting is done on
> > models
> > versus observation history so that given the model predictions, you can
> > predict the surface conditions. The result is called Model Output
> > Statistics or "MOS". To get enough data for statistics they break the
> > country up into separate regions and apply uniform statistics
> > throughout
> > each region. The text forecasts are usually based on MOS.
> >
> > We had the lead MOS guy from NOAA in talking about what they do. He
> > showed a map of the different regions, and one of the borders follows
> > the
> > MD-PA line.
> >
> > Gee...guess where High Rock is? I would suppose if you average the HR
> > and
> > Pulpit text forecasts you may get a good approximation to the correct
> > HR
> > forecast. Or maybe the HR forecast will be closer to the Pulpit
> > forecast
> > due to being on the Pulpit side of the mountain range. Anyone noticed
> > long term trends to back this up?
> >
> > Brian Vant-Hull
> > 301-646-1149
> >
> >
>
>
>
>
>
User avatar
TQ
Posts: 42
Joined: Thu Feb 10, 2005 5:34 pm
Location: KPTB
Contact:

weather prediction and HR

Post by TQ »

OK. Wanted to be sure you were referring to raw MOS forecasts or other NWP
data.

The difference then is most likely a result of Pulpit forecast coming from
the NWS office in State College v. the NWS forecast issued by Sterling.

-----Original Message-----
From: Vant-Hull - Brian [mailto:brianvh@umd5.umd.edu]
Sent: Saturday, March 12, 2005 08:36 a.m.
To: hg_forum@chgpa.org
Subject: RE: weather prediction and HR



Yesterday's NWS text forecast. I just got them straight from the chgpa
webpage HR and pulpit links.

Brian Vant-Hull
301-646-1149

On Fri, 11 Mar 2005, ToweringQs wrote:

>
> I am curious to know where the disparate forecasts are posted.
>
> -----Original Message-----
> From: Vant-Hull - Brian [mailto:brianvh@umd5.umd.edu]
> Sent: Friday, March 11, 2005 04:58 p.m.
> To: hg_forum@chgpa.org
> Subject: weather prediction and HR
>
>
>
> Seeing that the pulpit is predicted as 10-20 mph and 50% snow versus HR
> predicted to be 5-10 and no snow reminds me of something I just saw in my
> statistics for meteorology class I saw yesterday.
>
>
>
>
>
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