The enduring fog and low cloud episode of 5-10 December 2015: Big Bubble Fog Trouble

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1 1. Overview The enduring fog and low cloud episode of 5-10 December 2015: Big Bubble Fog Trouble By Richard H. Grumm National Weather Service State College, PA An enduring low cloud and fog episode affected much of the eastern United States from 5 to 10 December In the early stages the low clouds and fog affected much of the eastern United States from Indiana to the East Coast but persisted for a longer period over central Pennsylvania (Fig. 1). The persistent low clouds and fog were likely due to several contributing factors including unfrozen ground, wet ground due to recent rainfall (Fig. 2), and the combination of high pressure and weak flow near the surface. (Fig. 3). The regional temperatures over much of the east were well above normal in early December and there was no frost in the ground. The rains on 1-3 December (Fig. 2), which peaked on 2 December provided moisture in the upper levels of the normally frozen soil. A weak surge of cold air followed the rain event which lowered the dew points over the eastern United States (Fig. 4). This created a period of sharp diurnal temperature swings with afternoon dew points mainly in the 30s and overnight lows in the 20s. The mean pattern from 0000 UTC 5-10 December 2015 (Fig. 5) showed above normal heights and 850 hpa temperatures over much of the United States and a strong and persistent anticyclone along the East Coast over the 5 day period. The precipitable water (PW) values were relatively low implying with weak flow relatively good conditions for radiational cooling. The 850 hpa temperatures (Fig. 6) were near to above normal during most of this period in the eastern United States. On 7 December dense valley fog produced rime ice in low lying valleys which produced icy road ways. The ice crystals fell from trees and there were reports and pictures in one location of ice needles coating the ground between State College and Bellefonte, PA. The ice needles were attributed to the presence of ice nuclei and additional moisture in the region. The ice needles were all observed within a mile of a sewage treatment plant. The strong inversion (Fig. 7) in State College may have trapped anthropogenic particles which served as condensation and ice nuclei. Observations on both the 6 th and 7 th of December indicated a rare occurrence of temperatures 10F warmer on the ridge tops then in the valleys. Smoke plumes during the 6 th from houses burning traceable smoke were trapped by a visible inversion about feet above the valley floor. The impacts of the event in central Pennsylvania included freezing fog which reduced visibilities to below ¼ mile, icy roads and walkways. The rim also coated trees and other surface. There were abundant pictures of hoarfrost and rime from 5-9 December received by the National

2 Weather Service via social media and . Hoarfrost images were dominant on the 5 th and 6 th with more rime ice images from the 7 th to the 9 th. Second impact of the fog and low clouds were large temperature forecast errors. Valley locations were often 5-10F colder than forecast. Along the ridge tops were temperatures peaked in the 40s and 50s throughout the event the temperature forecasts were more realistic. Forecast errors were pronounced in the NCEP GEFS (Fig. 8 lower), SREF 1 (Fig. 8), and 3km HRRR (Fig. 9). These systems all had difficulties keeping low-level cold air in the valleys implying poor boundary layer representation and physics in these forecast systems. The GEFS at 33km is probably the most likely system to suffer from extreme coarse resolution. Forecasts of the dissipation of the fog and low clouds proved to be problematic. Nearly all guidance did not hold onto the fog and low clouds long enough. On 7-9 December the low clouds never exited most deep and narrow valleys. The 3km HRRR (not shown) typically kept the cold air and low clouds around in the morning but dissipated leading to the warm 2m temperature forecasts (Fig. 9). The best system and it too was too fast to erode the fog and low clouds was the experimental HRRR-X. To the HRRR-X credit it held the low-clouds and cold air in longer and the 2m temperature fields indicated more enduring cold air in the valley locations (Figs. 10 & 11) where clouds persisted longer. For illustrative purposed only 1 forecast cycle of the HRRR-X is shown. Several cycles and several days were shown. Both on the 8 th (Figs 10 & 11) and the 9 th (not shown) even the HRRR-X was too fast in scouring out the low clouds and low ceilings. To its credit it clearly outperformed all examined guidance. A persistent period of relative cold, fog, and low clouds affected central Pennsylvania from 5-10 December The first 2 days were not as foggy and the clouds lifted in most areas. Freezing fog was observed from the 6-9 December which created a very localized hazardous roads on the 6 th and 7 th with the most intense riming and icing on the 7 th. Most valley locations remained 5-10F colder than models and guidance forecasts during the event. The event was not well forecast from the perspective of the persistence of the low clouds and fog. This lead to erroneous high temperature forecasts. The boundary layer physics have problems with low-level cold air and this event highlighted these issues. During the winter of it was observed that the 3km HRRR did better than all other guidance keeping shallow cold air and freezing rain in the valleys of central Pennsylvania. Successive runs often showed a slower eroding of the cold air. Similar to the cold air low clouds, during these freezing rain events, ultimately the cold air lingered longer than the HRRR indicated. Then new HRRR-X which will replace the HRRR in early 2016 may provide better guidance in shallow cold air and thus freezing rain events. However, all of these systems have some serious planetary boundary layer issues when dealing with shallow cold air in valleys. 1 Using the 7 December GEFS 2m temperatures forecast at 0000 and 0600 UTC were about 50F. The 12Z run was colder. A similar trend was observed in the SREF. Both systems were too warm.

3 2. Acknowledgements Stan Benjamin of GSD provided links and insights into the new 3km HRRR-X. GSD HRRR page is at 3. References

4 Figure 1. Visible imagery of the fog and low clouds on 5, 6 and 7 December 2015.

5 Figure 2. Stage IV total accumulated rainfall for the period of 0000 UTC 1 to 1200 UTC 3 December Return to text.

6 Figure 3. CFS mean sea-level pressure pattern in 24 hour increments from a) 1200 UTC 4 to f) 1200 UTC 9 December Return to text.

7 Figure 4. Daily trace of temperatures and dew points from 2-9 December for Davis weather station site KPASTA18 in State College, PA. Return to text.

8 Figure 5. CFS composite mean pattern for the 5 days from 0000 UTC 5-10 December Data include mean and standard deviation of a) 500 hpa heights, b) 850 hpa temperatures, c) mean sea level pressure, and d) precipitable water. Return to text.

9 Figure 6. As in Figure 3 except for 850 hpa temperatures and anomalies. Return to text.

10 Figure 7. RUC sounding at a point near State College at 1200 UTC 7 December. The shallow cold layer was below the inversion with dry and warm air aloft. Sounding provided by Jon Nese (PSU) who also provided images of both rime and hoarfrost. Return to text.

11 Figure 8. One example of NCEP GEFS and SREF forecasts of 2m temperatures at a point near State College, PA. Many locations in and near State College remained in the 30s 6-9 December. The locations varied markedly based on elevation and the enduring nature of the low clouds over the valley. Return to text.

12 Figure 9. NCEP 3km HRRR 2m temperature forecasts from 1200 UTC 7 and 8 December 2015 showing the maximum warm period on the 7 th and 8 th respectively during the 2 days of most persistent and widespread fog and low clouds. Return to text.

13 Figure 10. HRRR-X forecasts from 1100 UTC 8 December showing the hourly 2m temperatures with winds near the time of the peak 2km temperatures. The maximum was forecast around 1900 and 2000 UTC similar to the NCEP HRRR (Fig. 9) which was several degrees F warmer. Return to text.

14 Figure 11. As in Figure 10 except for the HRRR-X showing ceiling (kft) form the 1100 UTC HRRR-X forecasts valid hourly from UTC. These were the best forecasts when comparing the NCEP 3km HRRR and the GSD HRRR-X so only the HRRR-X is shown. Return to text.

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17 METAR Observations KUNV :55 METAR KUNV Z AUTO 22005KT 10SM CLR 07/05 A2985 RMK AO2 T :35 METAR KUNV Z AUTO 28008KT 7SM CLR 05/04 A2985 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 7SM CLR 05/04 A2983 RMK AO2 T :55 METAR KUNV Z AUTO 30003KT 7SM SCT120 06/05 A2984 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 5SM BR SCT120 05/04 A2985 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 5SM BR CLR 05/04 A2986 RMK AO2 T :55 METAR KUNV Z AUTO 26003KT 10SM CLR 07/05 A2987 RMK AO2 T :35 METAR KUNV Z AUTO 28005KT 10SM CLR 07/05 A2988 RMK AO2 T :15 METAR KUNV Z AUTO 27004KT 10SM CLR 07/05 A2988 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 10SM CLR 06/04 A2988 RMK AO2 T :53 METAR KUNV Z 00000KT 10SM SKC 07/05 A :53 METAR KUNV Z 22004KT 10SM SCT080 07/04 A :53 METAR KUNV Z 26006KT 10SM SKC 08/04 A :53 METAR KUNV Z 00000KT 10SM SKC 08/04 A :53 METAR KUNV Z 00000KT 10SM SCT060 09/04 A :53 METAR KUNV Z 20006KT 10SM SKC 10/05 A :53 METAR KUNV Z 20006KT 7SM SKC 11/05 A :53 METAR KUNV Z 20006KT 7SM SKC 10/06 A :53 METAR KUNV Z 21005KT 7SM SKC 10/07 A :53 METAR KUNV Z 00000KT 5SM BR SKC 07/07 A :35 METAR KUNV Z 00000KT 2SM BR SKC 06/06 A :25 METAR KUNV Z 00000KT 5/16SM FG OVC001 05/05 A :53 METAR KUNV Z 15003KT 1/8SM FG OVC001 05/05 A :53 METAR KUNV Z 15003KT 1/8SM FG OVC001 03/02 A :53 METAR KUNV Z 15003KT 1/8SM FG OVC001 01/01 A :53 METAR KUNV Z 15003KT 1/8SM FG OVC001 01/01 A :30 METAR KUNV Z 21003KT 1/8SM FG BKN001 01/01 A :10 METAR KUNV Z 21003KT 1/2SM FG SCT001 01/01 A :53 METAR KUNV Z 21003KT 2SM BR SCT043 02/02 A :53 METAR KUNV Z 21003KT 2SM BR SCT043 03/02 A :35 METAR KUNV Z AUTO 21003KT 1 1/2SM BR OVC043 03/03 A2994 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1 3/4SM BR OVC045 03/03 A2993 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 2SM BR SCT020 BKN029 OVC047 04/03 A2993 RMK AO2 T :35 METAR KUNV Z AUTO 22003KT 2SM BR BKN020 OVC029 04/03 A2993 RMK AO2 T :15 METAR KUNV Z AUTO 22003KT 2 1/2SM BR SCT020 OVC030 04/03 A2993 RMK AO2 T :55 METAR KUNV Z AUTO 24004KT 2SM DZ OVC020 04/03 A2992 RMK AO2 LTG DSNT S T :35 METAR KUNV Z AUTO 26007KT 2 1/2SM BR SCT024 BKN036 OVC042 04/03 A2992 RMK AO2 T :15 METAR KUNV Z AUTO 26006KT 2 1/2SM BR BKN045 OVC050 04/03 A2992 RMK AO2 T :55 METAR KUNV Z AUTO 26004KT 2SM BR SCT033 BKN047 OVC050 04/03 A2991 RMK AO2 T :35 METAR KUNV Z AUTO 27003KT 2SM BR SCT028 SCT034 OVC045 04/03 A2991 RMK AO2 T

18 :15 METAR KUNV Z AUTO 25003KT 2SM BR SCT035 BKN041 OVC050 04/03 A2991 RMK AO2 T :55 METAR KUNV Z AUTO 22003KT 2SM BR SCT019 OVC038 04/03 A2991 RMK AO2 T :35 METAR KUNV Z AUTO 26003KT 2SM BR OVC019 04/03 A2991 RMK AO2 T :15 METAR KUNV Z AUTO 25004KT 2SM BR SCT008 OVC021 04/03 A2991 RMK AO2 T :55 METAR KUNV Z AUTO 25004KT 2SM BR BKN008 OVC023 04/03 A2991 RMK AO2 T :35 METAR KUNV Z AUTO 26004KT 2SM BR OVC008 04/03 A2990 RMK AO2 T :15 METAR KUNV Z AUTO 26003KT 2SM -DZ BKN006 BKN028 OVC033 04/03 A2990 RMK AO2 T :55 METAR KUNV Z AUTO 25003KT 2SM -RA BKN006 OVC033 04/03 A2991 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 2SM DZ BKN006 OVC041 04/03 A2990 RMK AO2 P0001 T :15 METAR KUNV Z AUTO 23003KT 2 1/2SM -RA BKN006 BKN039 OVC045 04/03 A2991 RMK AO2 P0001 T :55 METAR KUNV Z AUTO 00000KT 2 1/2SM -RA OVC006 04/03 A2991 RMK AO2 T :35 METAR KUNV Z AUTO 17004KT 2 1/2SM DZ OVC006 04/03 A2991 RMK AO2 T :15 METAR KUNV Z AUTO 23008KT 3SM -DZ OVC006 04/03 A2992 RMK AO2 T :55 METAR KUNV Z AUTO 19004KT 3SM BR OVC006 04/03 A2991 RMK AO2 T :53 METAR KUNV Z 21006KT 4SM BR OVC008 04/03 A :53 METAR KUNV Z 21006KT 5SM BR OVC008 04/03 A :53 METAR KUNV Z 00000KT 5SM BR OVC008 04/02 A :53 METAR KUNV Z 00000KT 5SM BR OVC010 04/02 A :53 METAR KUNV Z 00000KT 4SM BR OVC010 04/02 A :53 METAR KUNV Z 00000KT 3SM BR OVC010 04/03 A :53 METAR KUNV Z 00000KT 3SM BR OVC008 03/03 A :53 METAR KUNV Z 00000KT 3SM BR OVC006 03/02 A :53 METAR KUNV Z COR 00000KT 2SM BR BKN006 OVC011 02/02 A :53 METAR KUNV Z 00000KT 11/4SM FG OVC001 00/00 A :30 METAR KUNV Z 00000KT 3/4SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 1/8SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M03 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M03/M03 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3006 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3006 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3006 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3005 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M02 A3005 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3005 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M02/M02 A3005 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M02 A3006 RMK AO2 T

19 :55 METAR KUNV Z AUTO 35003KT 1/4SM FZFG OVC001 M01/M01 A3007 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M01 A3007 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M02 A3007 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M01 A3006 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M01 A3006 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M01/M01 A3005 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M01/M01 A3006 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 00/00 A3006 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 00/00 A3007 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 00/00 A3007 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FG OVC001 00/00 A3007 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT M1/4SM FG OVC001 00/00 A3007 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT M1/4SM FG OVC001 00/00 A3007 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FG OVC001 00/00 A3007 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT M1/4SM FG OVC001 00/00 A3007 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FG OVC001 00/00 A3008 RMK AO2 T :53 METAR KUNV Z 00000KT 1/8SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 5/16SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 2SM BR OVC003 00/00 A :53 METAR KUNV Z 00000KT 3SM BR OVC005 01/00 A :53 METAR KUNV Z 00000KT 2SM BR OVC003 01/00 A :53 METAR KUNV Z 00000KT 2SM BR OVC003 01/00 A :53 METAR KUNV Z 00000KT 2SM BR OVC003 01/01 A :25 METAR KUNV Z 00000KT 2SM BR OVC001 01/00 A :53 METAR KUNV Z 00000KT 1SM BR OVC001 00/00 A :30 METAR KUNV Z 00000KT 1/2SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 1/4SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 1/8SM FG OVC001 00/00 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M01/M01 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M01/M01 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M01/M02 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :53 METAR KUNV Z 03003KT 1/8SM FZFG OVC001 M02/M02 A :30 METAR KUNV Z 00000KT 1/4SM FZFG OVC001 M02/M02 A :07 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :06 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M02/M02 A :53 METAR KUNV Z 00000KT 1/4SM FG OVC001 M02/M02 A :35 METAR KUNV Z AUTO 00000KT 3/4SM BR OVC001 M01/M02 A3012 RMK AO2 T :15 METAR KUNV Z AUTO 03003KT 1/4SM FZFG OVC001 M02/M02 A3011 RMK AO2 T :55 METAR KUNV Z AUTO 01003KT 1/4SM FZFG OVC001 M02/M02 A3011 RMK AO2 T :35 METAR KUNV Z AUTO 02005KT 1/4SM FZFG OVC001 M02/M03 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 05003KT 1/2SM FZFG OVC001 M04/M05 A3010 RMK AO2

20 T :55 METAR KUNV Z AUTO 00000KT 1/2SM FZFG BKN001 OVC075 M04/M05 A3011 RMK AO2 T :35 METAR KUNV Z AUTO 02003KT 3SM BR SCT001 M03/M03 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 30003KT 5SM BR CLR M02/M02 A3011 RMK AO2 T :55 METAR KUNV Z AUTO 03004KT 5SM BR CLR M02/M02 A3010 RMK AO2 T :35 METAR KUNV Z AUTO 01005KT 7SM CLR M02/M02 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 02003KT 7SM CLR M01/M02 A3010 RMK AO2 T :55 METAR KUNV Z AUTO 02004KT 5SM BR CLR M01/M02 A3010 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 4SM BR CLR M01/M01 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 7SM CLR M01/M02 A3011 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 5SM BR CLR M01/M01 A3012 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 5SM BR CLR M01/M02 A3012 RMK AO2 T :15 METAR KUNV Z AUTO 07003KT 10SM CLR M01/M02 A3012 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 10SM CLR 01/M01 A3012 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 10SM CLR 00/M02 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 10SM CLR 00/M01 A3011 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 10SM CLR 00/M01 A3011 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 10SM CLR 00/M01 A3011 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 10SM CLR 00/M01 A3011 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 10SM CLR 01/M01 A3011 RMK AO2 T :53 METAR KUNV Z 00000KT 10SM SKC 02/00 A :53 METAR KUNV Z 00000KT 10SM SKC 03/00 A :53 METAR KUNV Z 00000KT 10SM SKC 02/00 A :53 METAR KUNV Z 00000KT 10SM SKC 04/01 A :53 METAR KUNV Z 00000KT 10SM SKC 06/01 A :53 METAR KUNV Z 00000KT 10SM SKC 08/03 A :53 METAR KUNV Z 00000KT 10SM SKC 08/02 A :53 METAR KUNV Z 00000KT 10SM SKC 07/02 A :53 METAR KUNV Z 00000KT 9SM SKC 04/04 A :33 METAR KUNV Z 00000KT 8SM FEW001 03/02 A :09 METAR KUNV Z 00000KT 6SM BR FEW001 02/02 A3015 RMK VIS E 2SM :53 METAR KUNV Z 00000KT 1SM BR SCT001 00/00 A3016 RMK VIS NW 7SM :17 METAR KUNV Z 00000KT 6SM BR SCT001 00/00 A3018 RMK VIS E 1/2SM :07 METAR KUNV Z COR 00000KT 1/2SM FG BKN002 00/00 A3018 RMK VIS NW 7SM :53 METAR KUNV Z 14003KT 2SM BR SKC 00/00 A :53 METAR KUNV Z 00000KT 2SM BR SKC M03/M03 A :29 METAR KUNV Z 00000KT 2SM BR SKC M04/M04 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M05/M05 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M05/M06 A :53 METAR KUNV Z 00000KT 1/8SM FZFG OVC001 M06/M07 A :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M05/M06 A3018 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M05/M05 A3019 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M05/M05 A3018 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M05 A3019 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M05 A3020 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M05 A3021 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M05 A3021 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M05 A3021 RMK AO2

21 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M04/M04 A3022 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT M1/4SM FZFG OVC001 M04/M04 A3023 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M03/M04 A3023 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M03/M04 A3023 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M04/M04 A3023 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 1 3/4SM BR VV007 M03/M03 A3023 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1 1/4SM BR BKN001 M03/M03 A3023 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 1/4SM FZFG OVC001 M03/M04 A3023 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 5SM BR CLR M03/M04 A3024 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 5SM BR CLR M03/M03 A3025 RMK AO2 T :35 METAR KUNV Z AUTO 00000KT 4SM BR CLR M03/M03 A3025 RMK AO2 T :15 METAR KUNV Z AUTO 00000KT 2SM BR CLR M03/M03 A3025 RMK AO2 T :55 METAR KUNV Z AUTO 00000KT 1/2SM FZFG VV005 M03/M03 A3025 RMK AO2 T

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