B757 crew was required to divert to an offline station because of destination and alternate WX.

Attributes
ACN	444504
Time
Date	199907
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : dbq.vortac
State Reference	IA
Altitude	msl single value : 37000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp.artcc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Navigation In Use	other other vortac
Flight Phase	cruise : holding
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	444504
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	inflight encounter : weather non adherence : published procedure non adherence : far non adherence : company policies
Independent Detector	other flight crewa
Resolutory Action	flight crew : diverted to another airport
Supplementary
Problem Areas	Weather
Primary Problem	Weather

Narrative:

Used msn as an alternate airport, not authority/authorized for B757. While holding at dbq for unforecast thunderstorms at ord, were given further efc that made a divert a necessity. We advised dispatch and we opted for mke. We had no alternate filed at time of departure as the forecast was good. ATC advised us that we would have at least 1 hour more holding for mke due large number of diverts to there. I felt we could now get fuel critical as the WX was moving and appeared to be expanding its scope, so decided to land as soon as possible using my emergency authority/authorized at msn. Unable to contact dispatch with new destination.

Original NASA ASRS Text

Title: B757 CREW WAS REQUIRED TO DIVERT TO AN OFFLINE STATION BECAUSE OF DEST AND ALTERNATE WX.

Narrative: USED MSN AS AN ALTERNATE ARPT, NOT AUTH FOR B757. WHILE HOLDING AT DBQ FOR UNFORECAST TSTMS AT ORD, WERE GIVEN FURTHER EFC THAT MADE A DIVERT A NECESSITY. WE ADVISED DISPATCH AND WE OPTED FOR MKE. WE HAD NO ALTERNATE FILED AT TIME OF DEP AS THE FORECAST WAS GOOD. ATC ADVISED US THAT WE WOULD HAVE AT LEAST 1 HR MORE HOLDING FOR MKE DUE LARGE NUMBER OF DIVERTS TO THERE. I FELT WE COULD NOW GET FUEL CRITICAL AS THE WX WAS MOVING AND APPEARED TO BE EXPANDING ITS SCOPE, SO DECIDED TO LAND ASAP USING MY EMER AUTH AT MSN. UNABLE TO CONTACT DISPATCH WITH NEW DEST.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.