Currently reporting:
KJYO LEESBURG/GODFREY distance: 4.54 miles. WNW
@ 2019-06-20  23:15 UTC,
     KJYO 202315Z AUTO 33004KT 10SM CLR 28/21 A2956 RMK AO2
KIAD WASH DC/DULLES distance: 7.89 miles. SSE
@ 2019-06-20  22:52 UTC,
     KIAD 202252Z 24006KT 10SM FEW060 SCT090 BKN150 28/18 A2954 RMK AO2 RAB09E22 SLP998 P0000 T02780183
KGAI GAITHERSBURG distance: 19.18 miles. ENE
@ 2019-06-20  22:56 UTC,
     KGAI 202256Z AUTO 30005KT 10SM BKN065 28/20 A2955 RMK AO2 LTG DSNT SE SLP013 T02780200 PNO $
KHEF MANASSAS MUNI distance: 22.66 miles. S
@ 2019-06-20  22:56 UTC,
     KHEF 202256Z 20010KT 10SM FEW100 24/21 A2954 RMK AO2 LTG DSNT E TSB00E39 SLP011 T02440211 PNO $
KFDK FREDERICK distance: 26.56 miles. NNE
@ 2019-06-20  22:47 UTC,
     KFDK 202247Z 30011G15KT 10SM BKN120 28/19 A2956
KDCA WASHINGTON/NATL distance: 27.83 miles. ESE
@ 2019-06-20  23:12 UTC,
     KDCA 202312Z 22014KT 10SM -RA SCT050CB SCT060 BKN120 BKN250 27/21 A2952 RMK AO2 WSHFT 2257 CB E-S MOV E P0000 T02670206
KDAA FORT BELVOIR/DAV distance: 28.43 miles. SE
@ 2019-06-20  22:59 UTC,
     KDAA 202259Z AUTO 00000KT 10SM VCTS SCT046 SCT100 24/21 A2952 RMK AO2 RAE59 SLP999 $
KCGS COLLEGE PARK distance: 30.92 miles. E
@ 2019-06-20  23:23 UTC,
     KCGS 202323Z AUTO 32006KT 10SM SCT060 SCT120 29/19 A2952 RMK AO1 T02850187
KHWY WARRENTON distance: 34.12 miles. SSW
@ 2019-06-20  23:15 UTC,
     KHWY 202315Z AUTO 00000KT 10SM SCT060 BKN070 OVC110 27/19 A2955 RMK AO2 T02720189
KOKV WINCHESTER RGNL distance: 36.07 miles. W
@ 2019-06-20  23:15 UTC,
     KOKV 202315Z AUTO 26009KT 10SM BKN047 OVC110 26/18 A2958 RMK AO2
KMRB MARTINSBURG distance: 36.2 miles. NW
@ 2019-06-20  22:53 UTC,
     KMRB 202253Z 29007KT 10SM CLR 27/18 A2954 RMK AO2 SLP996 T02670183
KADW ANDREWS AFB distance: 36.87 miles. ESE
@ 2019-06-20  23:13 UTC,
     KADW 202313Z 23013G23KT 10SM -RA FEW038 SCT065 26/21 A2953 RMK AO2A LTG DSNT NE DZB2256E00RAB00 TSE13 PRESRR SLP004 $
KFME FORT MEADE distance: 38.76 miles. E
@ 2019-06-20  23:21 UTC,
     KFME 202321Z AUTO 29004KT 10SM SCT065 SCT080 SCT120 25/20 A2953 RMK AO1
KNYG QUANTICO MCAF distance: 39.15 miles. SSE
@ 2019-06-20  22:56 UTC,
     KNYG 202256Z AUTO 33005KT 10SM -RA SCT043 BKN055 OVC095 24/22 A2954 RMK AO2 PK WND 30036/2224 WSHFT 2219 RAB2158E09B26 TSB11E39 SLP005 P0008 T02390217 $
KCJR CULPEPER distance: 40.76 miles. SSW
@ 2019-06-20  23:15 UTC,
     KCJR 202315Z AUTO 20003KT 10SM SCT060 BKN075 BKN085 27/20 A2956 RMK AO2 T02700199
KFRR FRONT ROYAL distance: 41.89 miles. WSW
@ 2019-06-20  23:15 UTC,
     KFRR 202315Z AUTO 25005G14KT 10SM OVC100 26/17 A2956 RMK AO1
KBWI BALTO/WASH INTL distance: 43.94 miles. ENE
@ 2019-06-20  22:54 UTC,
     KBWI 202254Z 31008G17KT 10SM FEW060 SCT120 BKN160 BKN250 29/18 A2950 RMK AO2 LTG DSNT E SLP989 T02890183
KRMN STAFFORD REGNL distance: 44.53 miles. S
@ 2019-06-20  23:15 UTC,
     KRMN 202315Z AUTO 00000KT 10SM SCT065 SCT080 BKN100 27/23 A2959 RMK AO2 T02720230
KDMW CARROLL CNTY distance: 46.43 miles. NNE
@ 2019-06-20  23:20 UTC,
     KDMW 202320Z AUTO 28004KT 10SM CLR 28/19 A2955 RMK AO2 LTG DSNT SE
KHGR HAGERSTOWN distance: 47.2 miles. NNW
@ 2019-06-20  22:53 UTC,
     KHGR 202253Z 26009KT 10SM CLR 27/18 A2955 RMK AO2 SLP008 T02670183
KDMH BALTIMORE/DWNTWN distance: 49.49 miles. ENE
@ 2019-06-20  22:54 UTC,
     KDMH 202254Z AUTO 30/17 A2949 RMK AO1 SLP986 T03000167

Not current (maybe part-time, military or newly obsolete)
KW32 CLINTON distance: 36.05 miles. SE
KRSP NSF THURMONT distance: 41.9 miles. N
KJWX FORT RITCHIE distance: 46.64 miles. N
KRYT FOUNTAIN DALE distance: 47.73 miles. N