# Presentation: 516813

## The Graphical Tropical Weather Outlook (GTWO): 2007 Results  and Changes for 2008

- National Hurricane Center Graphical TWO Team:
- Jamie Rhome	Dan Brown
- James Franklin	Chris Lauer
-     Chris Juckins	    Chris Landsea

## User Feedback from 2007 Experimental Phase

- Over 2800 total forms of written feedback including;
- 2207 surveys
- 1472 surveys during the first 2 months (7/15-9/15) of the experimental period
- ~600 emails to the webmaster
- ~5.6 million total web hits
- 91% Atlantic
- 9%   Pacific
- In terms of web hits, the GTWO was among the most popular products and surpassed the text TWO within the first 30 days of its launch on July 15th.

## Distribution of Respondent Affiliation

**62% of the respondents were individuals**

## Survey Highlights

- 98% of respondents that provided an answer feel the GTWO is an appropriate NWS product/service.
- 8.9: average technical rating (accuracy, timeliness, etc) on a scale from 1-10.
- Two-thirds gave a 9 or 10 rating
- 9.6: average rating regarding ease of use and interpretation
- Three-fourths gave a 10 rating
- Nearly 90% gave a 9 or 10 rating
- Two-thirds of respondents use the product daily or several times per day.

## Verification of 2007 Genesis Probabilities

## Verification by Categorical Bins

_**Atlantic**_

_**Forecast Range**_**	****   **_**Expected %**_**    **_**Verifying**_**      **_**# of Forecasts**_
**   ****0-10%   (Low)               5                    3                     389**
** ****20-50% (Medium)         28                  18                     263**
** ****60-100%  (High)            71                  66                      53**

_**East Pacific**_

**       **_**Categories for the 2008 Graphical TWO**_
-    **-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis from 20-50%**
**   ****-High-probability of genesis greater than 50%**

_**Forecast Range**_**	****   **_**Expected %**_**    **_**Verifying**_**      **_**# of Forecasts**_
**   ****0-10%   (Low)               6                    6                     179**
** ****20-50% (Medium)         26                  47                     162**
** ****60-100%  (High)            70                  90                      29**

- Note the large separation
- between categories

## Atlantic Genesis Forecasts 

**Atlantic Genesis Forecasts **
**48 h Prior to TC Formation**

**Approximate Hours Prior to Genesis**

|  | -44.5 | -38.5 | -32.5 | -26.5 | -20.5 | -14.5 | -8.5 | -2.5 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Andrea |   |   |   |   |   | DSA* | DSA* | DSA* |
| Barry |   |   |   |   | DSA* |   |   | 20 |
| Chantal | 30 | 30 | 30 | 30 | 30 | 40 | 50 | 50 |
| Dean |   | 20 | 40 | 60 | 60 | 80 | 70 | 60 |
| Erin | 30 | 30 | 60 | 70 | 70 | 70 | 90 | 90 |
| Felix | 30 | 30 | 30 | 30 | 40 | 40 | 60 | 90 |
| Gabrielle | 60 | 50 | 20 | 20 | 20 | 20 | 90 | 90 |
| Humberto | 30 | 40 | 40 | 40 | 30 | 40 | 40 | 80 |
| Ingrid | 0 | 10 | 20 | 10 | 20 | 20 | 30 | 30 |
| Ten | 70 | 70 | 70 | 80 | 70 | 80 | 90 | 90 |
| Jerry | 10 | 10 | 10 | 0 | 10 | 10 | 10 | 40 |
| Karen | 40 | 60 | 60 | 60 | 60 | 80 | 80 | 100 |
| Lorenzo | 20 | 20 | 20 | 30 | 60 | 60 | 60 | 80 |
| Melissa |   | 20 | 20 | 20 | 20 | 10 | 10 | 10 |
| Fifteen |   |   |   |   |   |   |   |   |
| Noel | 50 | 50 | 40 | 30 | 30 | 30 | 80 | 80 |
| Olga |   |   |   | DSA* | DSA* | DSA* | DSA* | DSA* |
| Avg. | 34 | 34 | 35 | 37 | 40 | 45 | 58 | 65 |

*******DSA issued outside of Hurricane Season**

## East Pacific Genesis Forecasts 

**East Pacific Genesis Forecasts **
**48 h Prior to TC Formation**

**Approximate Hours Prior to Genesis**

|  | -43 | -37 | -31 | -25 | -19 | -13 | -7 | -1 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Alvin | 30 | 40 | 50 | 70 | 60 | 60 | 50 | 90 |
| Barbara | 20 | 20 | 10 | 30 | 30 | 30 | 50 | 100 |
| Three-E | 10 | 0 | 0 | 10 | 30 | 30 | 30 | 30 |
| Four-E | 60 | 70 | 80 | 70 | 50 | 40 | 30 | 30 |
| Five-E | 10 | 40 | 30 | 30 | 40 | 60 | 60 | 60 |
| Cosme | 10 | 0 | 20 | 20 | 20 | 20 | 20 | 20 |
| Dalila |   |   | 10 | 10 | 20 | 20 | 40 | 70 |
| Erick | 30 | 20 | 20 | 20 | 20 | 20 | 20 | 20 |
| Flossie | 50 | 50 | 50 | 60 | 40 | 30 | 30 | 50 |
| Gil | 20 | 20 | 20 | 20 | 30 | 40 | 50 | 60 |
| Henriette |   |   | 20 | 20 | 20 | 30 | 50 | 50 |
| Ivo | 20 | 40 | 50 | 50 | 50 | 40 | 50 | 80 |
| Thirteen-E |   | 10 | 20 | 20 | 20 | 20 | 30 | 30 |
| Juliette |   | 10 | 20 | 40 | 60 | 80 | 90 | 90 |
| Kiko | 20 | 20 | 60 | 60 | 60 | 60 | 70 | 80 |
| Avg. | 25 | 26 | 31 | 35 | 37 | 39 | 45 | 57 |

## Changes for 2008

- Move the issuance times of the operational text Tropical Weather Outlook (TWO) and the experimental graphical TWO for both the Atlantic and East Pacific basins to synoptic time.
- Increase the availability of the graphical TWO from two times daily to four times daily.
- Include 3-tiered categorical genesis forecasts (color-coding) in the experimental graphical TWO.
-      		**-Low-probability of genesis less than 20%**
**     ****	****	****-Medium-probability of genesis between 20-50%**
**     ****	****	****-High-probability of genesis greater than 50%**

**   ****-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis between 20-50%**
**   ****-High-probability of genesis greater than 50%**

**   ****-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis between 20-50%**
**   ****-High-probability of genesis greater than 50%**

**   ****-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis between 20-50%**
**   ****-High-probability of genesis greater than 50%**

**   ****-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis between 20-50%**
**   ****-High-probability of genesis greater than 50%**

**   ****-Low-probability of genesis less than 20%**
**   ****-Medium-probability of genesis between 20-50%**
**   ****-High-probability of genesis greater than 50%**

## New 2008 TWO and GTWO Issuance Times Shown in Yellow with Old 2007 Issuance Times Shown in Orange

- New 2008 TWO and GTWO Issuance Times Shown in Yellow with Old 2007 Issuance Times Shown in Orange

- 2 AM EDT/ 1 AM EST Atlantic and Pacific TWO and experimental GTWO

- 5:30AM  ET Atlantic TWO

- 4 AM  PT Pacific TWO

- 11:30AM  ET Atlantic TWO and experimental GTWO

- 10 AM  PT Pacific TWO and experimental GTWO

- 8 AM EDT/ 7 AM EST Atlantic and Pacific TWO and experimental GTWO

- 2 PM EDT/1 PM EST Atlantic and Pacific TWO and experimental GTWO

- 8 PM EDT/ 7 PM EST Atlantic and Pacific TWO and experimental GTWO

- 5:30PM  ET Atlantic TWO

- 4 PM   PT Pacific TWO

- 10:30PM  ET Atlantic TWO and experimental GTWO

- 10 PM  PT Pacific TWO and experimental GTWO

**0000 UTC**

**0600 UTC**

**1200 UTC**

**1800 UTC**

- indicates approximate arrival time of numerical model guidance

## 2008 GTWO

- _[http://hurricanes.gov/gtwo-example1](file:///Example%201%20Graphical%20Tropical%20Weather%20Outlook.htm)_
- _[http://hurricanes.gov/gtwo-example2l](file:///Example%202%20Graphical%20Tropical%20Weather%20Outlook.htm)_

## Benefits of Proposed Changes

- Enhances the level of service provided to our users including:
- Increasing availability of the graphical TWO from 2 times daily to 4 times daily.
- Categorical genesis forecasts added to the graphical TWO.
- Allows better use of latest information and provides more timely information to users.
- Previously, the Atlantic TWOs were based on global model guidance that was 9 hours old; this latency will be reduced to 3 hours with the new issuance time.
- Change in issuance times allow better use of products.
- The current issuance times for the Atlantic TWO does not allow the information to be easily incorporated into the 5pm or 10pm local evening news programming.
- The current TWO schedule releases the Atlantic TWO after NWS WFO’s have already prepared and sent their forecasts.