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Post by kukblue1 on Sept 7, 2020 16:18:31 GMT -5
I understand you can have a CB with no LTG Or Thunder. However if your going to put a CB within 10 miles and no rain OHD vis 10 miles should be be some other remark like VCSH (DIR) or SHRA (Dir)
If your observing the CB wouldn't you also be Observing the rain shaft. I guess it would depend on your location and view. How do you fell about a CB with No Thunder or LTG? Thoughts on if you have heavy rain but the only LTG is DSNT it's night and you can't see the LTG due to the heavy rain. do you still throw in the CB DSNT Remark Do you put it OHD cause of the heavy rain? Just thinking out loud.
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Post by northwx on Sept 7, 2020 18:02:44 GMT -5
7900.5E, 10.18 - we are to report significant clouds. Unless the CB formed OHD, you saw it coming... Report CBs whether or not they are TS. The LTG DSNT is an ALDARS thing - if you observe it and ALDARS isn't picking it up, I'd report it anyway.
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Post by kukblue1 on Sept 7, 2020 18:59:43 GMT -5
7900.5E, 10.18 - we are to report significant clouds. Unless the CB formed OHD, you saw it coming... Report CBs whether or not they are TS. The LTG DSNT is an ALDARS thing - if you observe it and ALDARS isn't picking it up, I'd report it anyway. So It's night time (can't really observer the CB) you have moderate rain vis 3 miles overcast 4,000 ft. ALDARS is picking up LTG DSNT W you don't observer LTG due to the 3 miles vis. You Still throwing in the CB DSNT W cause ALDARS is picking up LTG or even CB OHD cause of the rain? |
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Post by northwx on Sept 8, 2020 18:45:09 GMT -5
Embedded CBs should be observable, even at night - is your cloud layer at convective altitude? Convective cloud height calc: dry bulb temp - dew point = ___ divided by 4.4 times 1000 = convective cloud base. It's a judgment call on your part whether that constitutes observing the CB - you should be able to see a darker portion of the cloud base that indicates a taller cloud embedded in your overcast - if nothing gives you an indication of CB present, IT'S NOT THERE. ALDARS is going to do what ALDARS does... and that not very well. It makes me grind my teeth to say it, but follow instructions for ALDARS. Dark adaptation is critical to being able to observe at night. Moderate rain can fall from stratus - CB might not be the cause. If ALDARS is the only source of info for CB DSNT W and I can't confirm it, I'd not report the CB as I didn't observe it and can't confirm ALDARS. I don't know where you are kukblue, but likely the reflection of your town lights on the cloud base will give you an indication, even in moderate rain, of darker and/or lower clouds indicating CB present. DSNT? If you can only seed 3SM, DSNT is not reportable - let ALDARS be to blame, and you be at peace.
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Post by kukblue1 on Sept 9, 2020 13:42:17 GMT -5
Embedded CBs should be observable, even at night - is your cloud layer at convective altitude? Convective cloud height calc: dry bulb temp - dew point = ___ divided by 4.4 times 1000 = convective cloud base. It's a judgment call on your part whether that constitutes observing the CB - you should be able to see a darker portion of the cloud base that indicates a taller cloud embedded in your overcast - if nothing gives you an indication of CB present, IT'S NOT THERE. ALDARS is going to do what ALDARS does... and that not very well. It makes me grind my teeth to say it, but follow instructions for ALDARS. Dark adaptation is critical to being able to observe at night. Moderate rain can fall from stratus - CB might not be the cause. If ALDARS is the only source of info for CB DSNT W and I can't confirm it, I'd not report the CB as I didn't observe it and can't confirm ALDARS. I don't know where you are kukblue, but likely the reflection of your town lights on the cloud base will give you an indication, even in moderate rain, of darker and/or lower clouds indicating CB present. DSNT? If you can only seed 3SM, DSNT is not reportable - let ALDARS be to blame, and you be at peace. How do you feel about reporting a CB during the day and it's OVC005? You have a heavy rain shower overhead vis is down to 3/4 a mile. No LTG detected anywhere It's been overcast at that height for 8 hours. Can you report a CB in that case? |
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Post by northwx on Sept 9, 2020 17:46:58 GMT -5
ONLY if you have some reason to believe you have observed a CB. Is your convective altitude by the math 005? I'd think that highly unlikely. No CB will form above an OVC layer - the OVC will even out the convective instability and prevent the formation of the CB, so if the 005 is not your convective altitude, you have no CB. FAA rule of thumb: you may not report anything you can't directly observe... I wish they'd put that in the 7900.5 in so many words.
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Post by kukblue1 on Sept 9, 2020 19:02:55 GMT -5
ONLY if you have some reason to believe you have observed a CB. Is your convective altitude by the math 005? I'd think that highly unlikely. No CB will form above an OVC layer - the OVC will even out the convective instability and prevent the formation of the CB, so if the 005 is not your convective altitude, you have no CB. FAA rule of thumb: you may not report anything you can't directly observe... I wish they'd put that in the 7900.5 in so many words. d. Weather Not Observed. Observers are not required to report occurrences they have not observed. However, the observer may use information from reliable sources, for example, pilots, airline/airport personnel, a commissioned AWOS or other sources deemed acceptable by the observer. Weather Observers must not use the internet or other electronic systems not specifically approved by the FAA. Close to saying that. |
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Post by hlsto2 on Sept 9, 2020 19:06:19 GMT -5
7900 para 3.5.d. says we CAN report weather not "observed"...and that we may use sources we deem reliable. I deem radar and ltg loops reliable. satellite loops at night to help with high clouds.
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Post by northwx on Sept 10, 2020 15:01:05 GMT -5
We've been specifically warned (verbally) by Flight Service NOT to use pireps, due to liability issues, even if we know and trust the pilot. Only report what you can directly observe - and I agree with hlsto2 - though neither are available to us as we are outside radar coverage and sat loops are usually too late for our use and don't provide cloud heights. What's driving this is liability - stupid lawyers and their greedy clients in particular (though sometimes they're right...). If we report something that some pilot acts on and crashes, we're liable - do you really want to accept liability for something you didn't observe? Do you want to show up in court as an expert witness to the weather conditions and testify that you reported something you didn't directly observe? I didn't think so. I haven't had to go to court, but I have been deposed twice by the NTSB and the FAA as part of MSHP investigations involving fatalities... Our judgment of reliability of sources makes us liable.
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Post by hlsto2 on Sept 10, 2020 20:21:40 GMT -5
We've been specifically warned (verbally) by Flight Service NOT to use pireps, due to liability issues, even if we know and trust the pilot. Only report what you can directly observe - and I agree with hlsto2 - though neither are available to us as we are outside radar coverage and sat loops are usually too late for our use and don't provide cloud heights. What's driving this is liability - stupid lawyers and their greedy clients in particular (though sometimes they're right...). If we report something that some pilot acts on and crashes, we're liable - do you really want to accept liability for something you didn't observe? Do you want to show up in court as an expert witness to the weather conditions and testify that you reported something you didn't directly observe? I didn't think so. I haven't had to go to court, but I have been deposed twice by the NTSB and the FAA as part of MSHP investigations involving fatalities... Our judgment of reliability of sources makes us liable. I think we are covered by that paragraph. 7900 states the observer is responsible for the observation. and we assume that responsibility by having our initials on every metar and speci. I've been caught up in aircraft mishap investigations also. flight service can't tell us what sources to use or not use. |
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Post by hlsto2 on Sept 11, 2020 9:26:37 GMT -5
AWC-Aviation Weather Center aviationweather.gov is acceptable by the FAA as an internet weather source. this site is thru the NWS
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Post by hlsto2 on Sept 12, 2020 13:18:27 GMT -5
ONLY if you have some reason to believe you have observed a CB. Is your convective altitude by the math 005? I'd think that highly unlikely. No CB will form above an OVC layer - the OVC will even out the convective instability and prevent the formation of the CB, so if the 005 is not your convective altitude, you have no CB. FAA rule of thumb: you may not report anything you can't directly observe... I wish they'd put that in the 7900.5 in so many words. d. Weather Not Observed. Observers are not required to report occurrences they have not observed. However, the observer may use information from reliable sources, for example, pilots, airline/airport personnel, a commissioned AWOS or other sources deemed acceptable by the observer. Weather Observers must not use the internet or other electronic systems not specifically approved by the FAA. Close to saying that. close enough for me! |
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Post by tornado on Sept 13, 2020 10:31:27 GMT -5
Weather Observers must not use the internet or other electronic systems not specifically approved by the FAA. Aren't CWO vendors required to provide their CWO offices with a computer with internet access? If so, is that only to access AIS-R? |
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Post by hlsto2 on Sept 13, 2020 17:27:01 GMT -5
Weather Observers must not use the internet or other electronic systems not specifically approved by the FAA. Aren't CWO vendors required to provide their CWO offices with a computer with internet access? If so, is that only to access AIS-R? I believe the FAA contract directs the contractors to provide computers and internet access so that CWO's can access weather web sites. FA and A needs to quit worrying about CWO's and the internet and clean up the incompetent LAWRS mess. |
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Post by fractocu on Sept 14, 2020 9:15:43 GMT -5
Why are so many overthinking this. As an observer, you report what you OBSERVE with your EYES and EARS, outside in the elements. You don't "make things up". So....if you have a CB within 10 miles, you report the CB. You only report a rain-shaft IF you SEE it. If you have a 500 foot ceiling and a heavy downpour, you report exactly that. Now, if you have lightning, or hear thunder, you append CB to that 500 foot layer. You don't "make up" another layer to add the CB to. ALDARS is not a reliable source of info. for us. We've seen that in the studies done. I would not use ALDARS as a basis to report a nighttime CB. If there is lightning at night, you'll see it. I've been observing over 30 years (starting with the NWS in the 80's). Observing is pretty straightforward, don't overthink it!
Also, PIREPS can be used as a help, but, you make the final call. The pilot is making a judgement call of when he is breaking out of a layer. There can be a number of things that effect the accuracy of that call: is he/she looking at the layer exactly when they break out; when are they determining the break out to be (partially out of the layer, completely out of the layer); is virga playing a factor; etc?
Finally, radar is to be used as an aid to see what may be moving is your direction to help you prepare and get ready. If a line of what appears to be thunderstorms is heading your way, you now are extra vigilant, going out much more frequently so if that line holds together/intensifies, you are ready to report it right away.
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