Using GFE for Tropical Operations

Last Updated 10/6/2017

National Weather Service

Forecast Decision Training Division

Questions: Shannon.White@noaa.gov

Disclaimer    and   Privacy Notice

 

Viewing a New TCV
Adding Inland and/or Marine Zones to a Tropical Watch or Warning
Creating a Tropical Hazard Without a TCV
Storm Surge Collaboration
Creating Wind and HTI Elements

Creating the TCV, HLS, and MWW
Troubleshooting the TCV and HLS
Upgrading the Tropical Hazards

Finding and Resolving Hazard Conflicts

Removing Areas from Inland or Marine Tropical Hazards
Canceling/Ending Tropical Hazards

There are numerous grids, products, and services generated during a tropical event. From just a WFO perspective, the advisory cycle is incredibly busy, especially the hour prior to the advisory being issued by NHC. The general timeline to complete each of the various steps is below. For a larger image, click the timeline image below.

Run TCTornadoThreat  Run TCStormSurgeThreat Run TCFloodingRainThreat Run TCMWindTool Run PlotTPCEvents Edit Hazards grid Run TCWindThreat Generate Products

Viewing a new pre-TCV (Atlantic basin) or TCV (HFO and WR)

A GFE perspective must be running on your workstation.

1. An AlertViz banner will display notifying you a pre-TCV has arrived. The banner will instruct you to run the PlotTPCEvents from the Hazards menu.

2. Acknowledge the banner.

3. If hazards are currently separated into temporary hazard grids, finish your edits then click MergeHazards from the Hazards drop down menu. If the Hazard grid is locked by another user, the Hazard grid must be saved before continuing.

4. Under the Hazards drop down menu, click PlotTPCEvents. This will plot the NHC-issued tropical hazards into the Hazards grid. Click on the Hazards grid to view the NHC hazards.

Since the PlotTPCEvents operates directly on the Hazard grid, if other NHC hazards were in effect for part of the new area, the tool will take care of the needed replacements (i.e. HU.A becoming a HU.W).

5. Click on the blue disk to Save the Hazards grid. Ensure Hazard is selected and click Save Weather Elements.

 

Adding Local Zones to Center-Issued Tropical Hazard

Each WFO is responsible for issuing tropical storm and hurricane hazards for marine and inland zones. These hazards should closely match any NHC-issued coastal hazards in both area and threat. If a cyclone is expected to only affect marine zones or for inland sites who do not receive TCVs, follow these instructions.

1.Click on the Hazards grid to display the current hazards on the screen.

2. Click SeparateHazards from the Hazard drop down menu.

3. Pre-select the desired NHC-issued hazard and Click MakeHazard so it will populate the ETN box with the correct ETN.

4. Add zones as needed to the selected hazard. Be very careful not to remove or change any of the NHC-issued zones.

MakeHazard gui

5. Adjust the beginning and end times accordingly. The valid time in GHG should cover the expected time of the hazard. Remember that tropical hazards always receive an end time of 000000T0000Z (until further notice) in the TCV. The grid times are needed for the ZFP and CWF for expressions of uncertainty.

a.  If you need to further segment your marine zones for meteorological reasons, see the MWW section.

6. Click Run/Dismiss.

7. Repeat process for any other center-issued hazard to which you need to add zones.

a. If you are upgrading any hazards, make sure to delete the watch grids before proceeding.

8. In the Hazards drop down menu, click MergeHazards. If you have a Merge Conflict, resolve that before proceeding.

9. Click on the blue disk to Save the Hazards grid. Click Save Weather Elements.

10. If needed, add the storm surge hazards.

11. Create and transmit the MWW, TCV, and HLS.


Creating a Tropical Hazard with No TCV


As long as an advisory package is being issued for a storm, you can create tropical hazards and any needed products. These hazards should match the wind threat as indicated after running the TCMWindTool as well as hazards from neighboring offices.

1. Click on the Hazards grid to display the current hazards on the screen.

2. Click MakeHazard from the Hazard drop down menu.

3. Select Tropical Cyclone from the categories of hazards and choose the type of hazard you wish to create. 

MakeHazard gui

4. Using the slider bars on the right, choose the time frame for which you are forecasting the conditions to occur.

5. Left click and drag any inland or marine zone(s) you wish to add. They will become red when added.

6. Choose the advisory package from which to pull the ETN.

TCM choices

Failure to choose a TCM will result in one of 2 errors alerting you to a missing ETN. If these are received, click Acknowledge, follow the message and restore the MakeHazard window (do not open a new one) and fix the ETN selection.

No TCM chosen                    
Bad ETN

7. Click Run if other hazards need to be created or Run/Dismiss if this is your final hazard to be created.

8. Repeat process for any other hazard you wish to create. If you are upgrading any hazards, make sure to delete the watch grids before proceeding.

a.  If you need to further segment your marine zones for meteorological reasons, see the MWW section.

9. In the Hazards drop down menu, click MergeHazards. If you have a Merge Conflict, resolve that before proceeding.

10. Click on the blue disk to Save the Hazards grid. Click Save Weather Elements.

11. Create and transmit the TCV, HLS, and/or MWW.

Upgrading the Tropical Hazards

1. Click on the Hazards grid to display the current hazards on the screen.

2.
Follow either Adding Inland/Marine Zones to a Tropical Watch or Warning or Creating a Tropical Hazard with No TCV to create the new, upgraded hazard(s).

 

 

Finding and Resolving Hazard Conflicts

1. If a merge conflict is detected when running MergeHazards, note the grids and time frame involved from the error message, then click Cancel Merge to return to the separated hazards.

2. Click in the time range on one of the temporary hazard grids noted from the error message. Choose the one that you wish to still be in effect once this is resolved.

3. Click within the hazard (red) area, then click the right mouse button and choose Select Homogeneous Area. This creates and edit area where that hazard exists.

4. Switch to the other grid in question. The edit area likely overlaps with at least one zone of this hazard. Make sure None is highlighted on the color bar, then click the right mouse button and choose Assign Value. This removes the overlapping zone(s) from the conflicting hazard.

5. Proceed with merging your hazards.

 

 

Removing Areas from Existing hazards

1. Click on the Hazards grid to display the current hazards on the screen.

2. I
n the Hazards drop down menu, click SeparateHazards. A temporary hazard grid will be created for each hazard in effect.

3. Click on the tropical hazard grid you wish to edit, then click MakeHazard from the Hazard drop down menu.

4. Left click once on each red inland or marine zone you wish to remove. They will change to the default black background of the tool. See either Adding Local Zones to a Tropical Watch or Warning. Be careful to not remove any NHC-issued zone.

5. Click Run or Run/Dismiss at the bottom of the tool.

6. Repeat process for any other tropical hazard from which you wish to clear an area.

7. In the Hazards drop down menu, click MergeHazards. If you have a Merge Conflict, resolve that before proceeding.

8. Click on the blue disk to Save the Hazards grid. Click Save Weather Elements.

9. Create and transmit the TCV, HLS, and/or MWW.

 

Canceling/Ending Tropical Hazards

1. If coastal zones are part of the hazard, you MUST wait for the NHC TCV to be received, then run the PlotTPCEvents tool. Otherwise, proceed to step 2.

2. In the Hazards drop down menu, click SeparateHazards. A temporary hazard grid will be created for each hazard in effect.

3. Click on the hazard you wish to cancel, then right click and hold for menu.

4. Drag down to Delete Grid and release mouse button.

5. Repeat process for any other hazard you wish to end.

6. In the Hazards drop down menu, click MergeHazards.

7. Click on the blue disk to Save the Hazards grid. Click Save Weather Elements.

8. Create and transmit the TCV, HLS, and/or MWW.

 

Creating Wind and the HTI Elements

All Atlantic basin WFOs and HFO must create the Hurricane Threats and Impacts elements as they are required elements for running the TCV and HLS. The elements are WindThreat, FloodingRainThreat, TornadoThreat, and, if a coastal site, StormSurgeThreat.

 The Wind and WindGust grids also need to match the NHC forecast and be collaborated with your neighboring offices. This is accomplished through the use of the TCMWindTool.

TCMWindTool

Some keys for effectively creating Wind grids with the NHC-forecast cyclone are:

  1. Prior to the pre-TCM and pre-RCL arrival (around conference call time), prepare your background wind field using the model which is closest to the NHC forecast. Include all local effects, as needed.

    1. If the event is ongoing, your Wind grids should already be fairly close.

    2. Ideally you would not exceed the time steps provided by NHC in their official forecast (6-hourly). If hourly Wind grids are required, preparation of the background winds at each hour is key so the TCMWindTool can do the proper interpolation of the NHC forecast.

  2. When the pre-TCM and pre-RCL arrive (~45min before advisory), run the TCMWindTool with settings that match your neighboring WFOs.
                                                                  
                                                                                           

    1. An effort is underway to develop a wind reduction grid at all sites which should result in a better inland decay of a storm. The straight 15% reduction can result in an artificial weakening of a storm as it makes landfall when the opposite could be true.

  3. Tweaks to the resulting output can be made. But under NO circumstance should grids be removed and re-interpolated!  This can result in a very oddly jumping cyclone as GFE's interpolation scheme does not properly handle a moving cyclone. Only the TCMWindTool's Rankine vortex scheme results in proper cyclone movement.

  4. All offices should strive to complete Wind and subsequent WindGust editing around the same time so the NDFD is updated uniformly. The NDFD only updates twice an hour.

WindThreat

The TCWindThreat procedure takes the output of the PWSProcedure along with the Wind and WindGust grids that result from running the TCMWindTool and generates a WindThreat grid that can be used to guide planning and preparation for the event. The result is not a forecast but what people should reasonably prepare for. Based on the settings chosen, different wind speed probability thresholds are chosen for each of the four possible threat levels. The procedure also takes into account the deterministic wind values in your GFE domain (not just area of responsibility) to account for values that could potentially affect your area.

The default/typical setting uses lower thresholds for PWS guidance for each threat level. The thresholds move to higher percentages as you move to High and then Higher. Highest uses purely the Wind and WindGust grids to determine the threat.

The resulting threat is outlined as shown. Again, this is to guide planning; it is not a forecast.  

Run the procedure with values that match your neighbors and make sure to collaborate the output. These grids are mosaicked and used by regional and national customers to assess their risk.

 

StormSurgeThreat

This procedure must be run every advisory regardless of surge threat. The grids the procedure creates are required for all zones deemed by your site to be coastal.

NEW: A 5-minute video (mp4 or CamtasiaPlayer) is available on using the Manual options when pSurge is not being run.

The 2017 version of TCStormSurgeThreat adds the option to zero out tidal-only influences so the surge window reflects the main surge event. The rest of the options remain unchanged from previous seasons.

The procedure always creates InundationMax, InundationTiming, and StormSurgeThreat. For PHISH and ISC (if SSU ran with straight PETSS) options, the various datum grids (SurgeHtPlusTide) will also be created. The different procedure choices are summarized below:

 

If pSurge is available for this storm, use that along with the exceedance recommended by SSU. Recall that the guidance is based on the previous advisory's information. If storm is transitioning to post-tropical and SSU deems pSurge to no longer be representative, they will run with PETSS and those grids will be available for populating using ISC mode. If no model is available, use the Manual modes and input values up to 3 feet over pre-selected areas.

For Manual modes, ETSS or ESTOFS can be used to determine what values to use in the Inundation Height slider bar. Just make sure to properly account for datum differences when determining those values. For the first time running during an event, choose Manual Replace so all grids get created. Otherwise Manual Add can be used to modify the existing grids. For all Manual modes, an edit area over which the values will be assigned must be loaded first. Then choose the Inundation Height (0-3 ft.) and the hours over which that value will be experienced. Once grids have been created via Replace, different values can be created over different areas using Manual Add. 

The resulting threat grid is based on the InundationMax value at each grid cell.    

Run the procedure with values that match SSU recommendations and your neighbors and make sure to collaborate the output. If edits are needed to InundationTiming to remove tidal-only time steps, make sure to re-run with the UpdateInunMax option to bring the InundationMax and StormSurgeThreat in line with those edits

FloodingRainThreat

Beginning in 2017, the TCFloodingRainThreat procedure incorporates probabilistic QPF from WPC. For text/gridded FFG factor, 0 means that for areas without gridded FFG, no calculation will be done. This should be just fine, though. If text and gridded FFG blending is desired, empirical testing has shown that 0.75 is a good blending factor.

 

As it is with surge and wind, the default is 10%. But options are also there to use the 50% or to go strictly deterministic using only your local QPF.

The 10% option will use the max value between the 10% exceedance (90% percentile) PQPF data and the QPF in the Fcst db in the algorithm described below.

The 50% option will use the max value between the 50% exceedance (50% percentile) PQPF data and the QPF in the Fcst db in the algorithm described below.

Run the procedure with values that match your neighbors and make sure to collaborate the output. These grids are mosaicked and used by regional and national customers to assess their risk.

 

TornadoThreat

The TornadoThreat procedure uses various SPC guidance grids to generate a threat grid. The final grid is the highest threat at each gridpoint after interrogating each probability grid shown.

First the Day 1 ptor is used to generate an initial grid      

Then if the pxtor (prob of sig tor) for Day 1 is greater than 10% it bumps up any non-None areas by one category. For context, a ptor > 30% would be exceedingly rare for a tropical event.

Then Day 2 ptotsvr is used to determine threat  

Then if the Day 2 prob of sig tor is greater than 10% it bumps up any non-None areas by one category. For context, a Day 2 ptotsvr > 60% would be exceedingly rare for a tropical event.

Finally Day 3 is taken into account     If Day 3 prob of sig tor > 10% for any points, the Elevated would become Mod.

 

Storm Surge Collaboration

If the threat for life-threatening inundation exists, the NHC SSU will initiate the collaborative process that results in the storm surge watch/warning. The upcoming collaboration will be discussed on the hotline call so offices affected can expect the banner below to join the stormsurgecollaboration chatroom in NWSChat and to run CopyNHCProposed to generate an editable grid.

This procedure also creates a difference grid that shows where areas are recommended to be added or removed when compared to the last advisory. Recall that the guidance being used is from the previous advisory. If this is your first advisory with a SS W/W, the procedure will let you know no difference grid could be created.

Decide which areas to leave in the W/W and which areas may need to be removed. Pay special attention to zones outside of tropical wind warnings as those areas will not automatically be included in your WFO TCV unless they have at least 3% coverage in the SS W/W. Also collaborate with your neighboring WFOs on areas being modified. This can be accomplished both via chat and ISC.

Once your edits are complete, save your ProposedSS grid which shares your grid with both SSU and your neighboring WFOs. If SSU has any issues with your edits, that will be noted via chat or possibly a phone call.

Once SSU has approved of all edits, they will finalize the process and notify all WFOs collaboration is complete. You will receive another banner at this point prompting you to run MergeProposedSS to add the finalized SS W/W to your Hazards grid. If you attempt to run MergeProposedSS with unsaved, separated, or locked Hazards, you will be forced to rectify that before running again.

Creating the Products

 

1. If hazards are currently separated into temporary hazard grids, finish your edits then click MergeHazards from the Hazards drop down menu. If you have a Merge Conflict, resolve that before proceeding.

2.  Ensure you have the following grids complete:

                                          

3. Click on the blue disk to Save your grids. Click Save Weather Elements.

4. On the Products drop down menu, click Publish to Official. Make sure to publish all grids and all times!

5. Under the Products drop down menu, click Formatter Launcher.

6. In the Formatter Launcher window, click Products, then choose Hazard --> Hazard_TCV.

7. Choose the appropriate TCP for your storm. If pSurge has not been run for this storm yet, choose Do Not Populate. NHC is making a conscious effort to run pSurge the advisory before U.S. W/Ws will be needed.

    a. If you are trying to trigger downstream notification of NEW/UPG hazards (NWR/EAS/WEA) and current wind speed probability grids are not available, choose No. This will insert  
        placeholder wording in the product and eliminates the need for the PWS and WindThreat grids. It will, though, put placeholder wording in all non-surge sections.

    b. If you do issue a partial TCV for the above purpose, you must re-run the TCV shortly after the WSP grids arrive and you run the PWSProcedure and
        TCWindThreat. The NWS webpages and customer application will not contain useful information until a full TCV is issued!


                                            TCV GUI

8. Click Run.

9. Make sure the output looks correct. If anything looks out of order, correct the necessary grids and re-run the TCV. Do not edit the output.
    a. The hazards will have a hazard end time of 000000T0000Z for UFN. This is correct.

10. When you are ready, click Transmit to send the product. Click Transmit again on the transmit window which comes up to actually issue the product.

11. Check the GHG Hazards Monitor to ensure your hazards are there which verifies the transmit was successful. This transmit also saves off information which is required to run HLS.

12. In the Formatter Launcher window, click Products, then choose HLS (Hurricane Local Statement).

a. Ensure the Situation Overview has already been created by entering WRKHLS in the AFOS Cmd window (the one on the right side of the Text Window) and including the overview of the event for this advisory. Save that file so it will be imported when the HLS is run. Do not use any other editor than the text workstation as invisible characters can be introduced which cause the HLS to fail.

13. Make the appropriate selections on the interface. For Step 3, select only the hazards which present a real threat to the CWA and order them according to the impact they will have.  You do not have to choose all of the hazards, but at least one needs to be chosen. For Step 5, Conditions/Ongoing is to be chosen when the CWA is about 6 hours either side of 34 kt winds affecting your CWA.

                                        HLS Gui

14. Click Run.

15. Edit all framing code as appropriate and ensure WRKHLS was properly imported as the Situation Overview. In the Precautionary/Preparedness Actions section, make sure to not only trim down the list but to remove the phase wording intended to help you decide which information to keep.

As edits are made, make sure to leave the general format (e.g. ** around Main Headline, bullet format) as the formatter produced it.

                                        What to edit

a. If you selected No for WSP grids earlier when running the TCV, copy and save off the Changes to Watches and Warnings section but do not transmit this HLS.

b. If this is the HLS being created after a full TCV was issued, replace the empty/None Changes to Watches and Warnings section with the text saved off earlier.

16. Run Spell Check, correct any valid issues discovered, and click Transmit. Click Transmit again on the transmit window which comes up to actually issue the product.

17. If marine zones are involved, create and issue the Hazard_MWW as usual.
        a.  If you need to segment the MWW for meteorological reasons (e.g. some zones in TR.A will have 10 ft. seas while others will have 3-5 ft.), you can use the end time
             to force that separation since the ETN replaces the segmentation ability. When creating Hazards, make one set of zones end one hour before the rest, as shown.

           b.  Only make this change to the end time of the hazard. The end time is always UFN in the VTEC for tropical hazards and one hour difference should not negatively
             impact the Expressions of Uncertainty in the CWF.

        

 

 

Troubleshooting

The new TCV and HLS are very complex formatter which rely on a variety of grids, guidance, and other internal files. Feedback messages are provided to help guide you in case of issues.

1. The most common reason for a TCV formatter failure is one or more of the required grids was not generated. If this is the case, a list of missing weather elements, as shown.

If you have the listed element in your grid manager, then make sure to go back and publish ALL grids and ALL times.  It is best to use a weather element group that contains all of the required grids such as the baseline HTI weather element group.


                                                

2. A storm-based HLS cannot be generated unless a TCV has first been issued. Only a Dispel Rumors HLS can be created without first issuing a TCV. If you attempt to create an HLS without first issuing a TCV, you will receive the message below in your formatter launcher window.                              

                                            No TCV issued

        a. If a TCV was issued and a different forecaster is running the HLS and receives this message, then there are permission issues with the tcvAdvisories directory. This will need to be addressed by your ITO or the NCF.

3. At least one impact section must be chosen when running the HLS, even for the last HLS. If no impact sections are chosen, you will receive the following error in the formatter launcher window.

                                            Missing Impact section

4. For any other TCV or HLS failure, call the NCF and open a CRITICAL trouble ticket.