[EAS] Improving weather alerts on WEA mobile devices

[Sean Donelan]

WEA devices receive one of 15 message 3GPP codepoints in two languages.
8 codepoints are used for Imminent Threat alerts with 
Severity-Urgency-Certainty and the remaining 7 codepoints are used for 
everything else.

In the following, the Count is the number of matching WEA messages sent in 
2017. Typically, NWS uses static values for it's alerts. Civil alert 
originators mostly use the maximum value, but also use almost random
values for Severity-Urgency-Certainty.

Remember the EASCode is NOT transmitted through WEA to the mobile 
devices. The WEA device receives the CMAMtext or default text is 
generated from the EAS Code/Response Type. In either case, the 
opt-in/opt-out on the mobile device is determined by the WEA codepoints 
only, never the WEA text. Currently CMAS/WEA mobile devices do not use 
Certainty for opt-in/opt-out. Imminent Threat messages opt-in/opt-out 
based on 3GPP codepoints for Extreme Threat and Severe Threat; more or 
less.

There is special handling for Presidential, AMBER, and test messages. 
Again, using only the 3GPP codepoints on the mobile device.

EASCode	Severe	Urgent		Certain		Count
AVW	Extreme	Immediate	Observed	1
CAE	Special	Special		Special		184
CDW	Extreme	Immediate	Observed	6
CDW	Severe	Immediate	Observed	1
CEM	Extreme	Immediate	Observed	47
CEM	Extreme	Immediate	Likely	1
CEM	Severe	Immediate	Observed	10
CEM	Severe	Immediate	Likely	4
CEM	Severe	Expected	Observed	2
CEM	Severe	Expected	Likely	6
DSW	Severe	Expected	Likely	23
EQW	Severe	Immediate	Observed	1
EVI	Extreme	Immediate	Observed	12
EVI	Extreme	Immediate	Likely	1
EVI	Extreme	Expected	Likely	1
EVI	Severe	Immediate	Observed	3
EVI	Severe	Immediate	Likely	1
EWW	Extreme	Immediate	Observed	18
FFW	Severe	Immediate	Likely	3485
FRW	Extreme	Immediate	Observed	19
FRW	Extreme	Expected	Likely	1
FRW	Severe	Immediate	Observed	3
FRW	Severe	Expected	Observed	4
FRW	Severe	Expected	Likely	18
HMW	Extreme	Immediate	Observed	2
HUW	Extreme	Immediate	Likely	265
LAE	Extreme	Immediate	Observed	33
LAE	Extreme	Expected	Likely	2
LAE	Severe	Immediate	Observed	45
LAE	Severe	Immediate	Likely	20
LAE	Severe	Expected	Observed	4
LAE	Severe	Expected	Likely	9
LEW	Extreme	Immediate	Observed	15
LEW	Severe	Immediate	Observed	2
SPW	Extreme	Immediate	Likely	1
SPW	Severe	Immediate	Observed	1
SPW	Severe	Immediate	Likely	2
SSW	Extreme	Expected	Likely	75
TOR	Extreme	Immediate	Observed	2857

Changing the CMAS/WEA protocol to use Severity-Urgency-Category(Met). The 
count is the number of WEA message which would have matched.

The LAE messages using Met were from Grayson County, KY resending various 
NWS weather alerts as WEA messages.  Again, remember the EASCode is NOT 
transmitted through WEA to the mobile devices. WEA opt-in/opt-out is based 
on 3GPP codepoints only.

EASCode	Severe	Urgent		Cat	Count
CDW	Extreme	Immediate	Met	1
CEM	Severe	Immediate	Met	1
DSW	Severe	Expected	Met	23
EWW	Extreme	Immediate	Met	18
FFW	Severe	Immediate	Met	3485
HUW	Extreme	Immediate	Met	265
LAE	Severe	Immediate	Met	17
LAE	Severe	Expected	Met	5
SSW	Extreme	Expected	Met	75
TOR	Extreme	Immediate	Met	2857
AVW	Extreme	Immediate	Not-Met	1
CDW	Extreme	Immediate	Not-Met	5
CDW	Severe	Immediate	Not-Met	1
CEM	Extreme	Immediate	Not-Met	48
CEM	Severe	Immediate	Not-Met	13
CEM	Severe	Expected	Not-Met	8
EQW	Severe	Immediate	Not-Met	1
EVI	Extreme	Immediate	Not-Met	13
EVI	Extreme	Expected	Not-Met	1
EVI	Severe	Immediate	Not-Met	4
FRW	Extreme	Immediate	Not-Met	19
FRW	Extreme	Expected	Not-Met	1
FRW	Severe	Immediate	Not-Met	3
FRW	Severe	Expected	Not-Met	22
HMW	Extreme	Immediate	Not-Met	2
LAE	Extreme	Immediate	Not-Met	33
LAE	Extreme	Expected	Not-Met	2
LAE	Severe	Immediate	Not-Met	65
LAE	Severe	Expected	Not-Met	13
LEW	Extreme	Immediate	Not-Met	15
LEW	Severe	Immediate	Not-Met	2
SPW	Extreme	Immediate	Not-Met	1
SPW	Severe	Immediate	Not-Met	3
CAE	Special	Special		Special	184

I might suggest some different severity-urgency values, but I left them 
unchanged for this.  For example, a normal storm Flash Flood Warning might 
use Severe-Expected, while a dam/levee breach or the Ellicott City flood 
emergency might have used Extreme-Immediate. Or whatever the NWS hazard 
simplification alert levels eventually decide to use.